<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category  Zend
 * @package   Zend_Date
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd     New BSD License
 * @version   $Id: Date.php 24108 2011-06-04 00:09:27Z freak $
 */

/**
 * Include needed Date classes
 */
require_once 'Zend/Date/DateObject.php';
require_once 'Zend/Locale.php';
require_once 'Zend/Locale/Format.php';
require_once 'Zend/Locale/Math.php';

/**
 * @category  Zend
 * @package   Zend_Date
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Date extends Zend_Date_DateObject {
	private $_locale = null;
	
	// Fractional second variables
	private $_fractional = 0;
	private $_precision = 3;
	
	private static $_options = array ('format_type' => 'iso', // format for date strings 'iso' or 'php'
'fix_dst' => true, // fix dst on summer/winter time change
'extend_month' => false, // false - addMonth like SQL, true like excel
'cache' => null, // cache to set
'timesync' => null )// timesync server to set
;
	
	// Class wide Date Constants
	const DAY = 'dd';
	const DAY_SHORT = 'd';
	const DAY_SUFFIX = 'SS';
	const DAY_OF_YEAR = 'D';
	const WEEKDAY = 'EEEE';
	const WEEKDAY_SHORT = 'EEE';
	const WEEKDAY_NARROW = 'E';
	const WEEKDAY_NAME = 'EE';
	const WEEKDAY_8601 = 'eee';
	const WEEKDAY_DIGIT = 'e';
	const WEEK = 'ww';
	const MONTH = 'MM';
	const MONTH_SHORT = 'M';
	const MONTH_DAYS = 'ddd';
	const MONTH_NAME = 'MMMM';
	const MONTH_NAME_SHORT = 'MMM';
	const MONTH_NAME_NARROW = 'MMMMM';
	const YEAR = 'y';
	const YEAR_SHORT = 'yy';
	const YEAR_8601 = 'Y';
	const YEAR_SHORT_8601 = 'YY';
	const LEAPYEAR = 'l';
	const MERIDIEM = 'a';
	const SWATCH = 'B';
	const HOUR = 'HH';
	const HOUR_SHORT = 'H';
	const HOUR_AM = 'hh';
	const HOUR_SHORT_AM = 'h';
	const MINUTE = 'mm';
	const MINUTE_SHORT = 'm';
	const SECOND = 'ss';
	const SECOND_SHORT = 's';
	const MILLISECOND = 'S';
	const TIMEZONE_NAME = 'zzzz';
	const DAYLIGHT = 'I';
	const GMT_DIFF = 'Z';
	const GMT_DIFF_SEP = 'ZZZZ';
	const TIMEZONE = 'z';
	const TIMEZONE_SECS = 'X';
	const ISO_8601 = 'c';
	const RFC_2822 = 'r';
	const TIMESTAMP = 'U';
	const ERA = 'G';
	const ERA_NAME = 'GGGG';
	const ERA_NARROW = 'GGGGG';
	const DATES = 'F';
	const DATE_FULL = 'FFFFF';
	const DATE_LONG = 'FFFF';
	const DATE_MEDIUM = 'FFF';
	const DATE_SHORT = 'FF';
	const TIMES = 'WW';
	const TIME_FULL = 'TTTTT';
	const TIME_LONG = 'TTTT';
	const TIME_MEDIUM = 'TTT';
	const TIME_SHORT = 'TT';
	const DATETIME = 'K';
	const DATETIME_FULL = 'KKKKK';
	const DATETIME_LONG = 'KKKK';
	const DATETIME_MEDIUM = 'KKK';
	const DATETIME_SHORT = 'KK';
	const ATOM = 'OOO';
	const COOKIE = 'CCC';
	const RFC_822 = 'R';
	const RFC_850 = 'RR';
	const RFC_1036 = 'RRR';
	const RFC_1123 = 'RRRR';
	const RFC_3339 = 'RRRRR';
	const RSS = 'SSS';
	const W3C = 'WWW';
	
	/**
	 * Generates the standard date object, could be a unix timestamp, localized date,
	 * string, integer, array and so on. Also parts of dates or time are supported
	 * Always set the default timezone: http://php.net/date_default_timezone_set
	 * For example, in your bootstrap: date_default_timezone_set('America/Los_Angeles');
	 * For detailed instructions please look in the docu.
	 *
	 * @param  string|integer|Zend_Date|array  $date    OPTIONAL Date value or value of date part to set
	 * ,depending on $part. If null the actual time is set
	 * @param  string                          $part    OPTIONAL Defines the input format of $date
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 * @throws Zend_Date_Exception
	 */
	public function __construct($date = null, $part = null, $locale = null) {
		if (is_object ( $date ) and ! ($date instanceof Zend_TimeSync_Protocol) and ! ($date instanceof Zend_Date)) {
			if ($locale instanceof Zend_Locale) {
				$locale = $date;
				$date = null;
				$part = null;
			} else {
				$date = ( string ) $date;
			}
		}
		
		if (($date !== null) and ! is_array ( $date ) and ! ($date instanceof Zend_TimeSync_Protocol) and ! ($date instanceof Zend_Date) and ! defined ( $date ) and Zend_Locale::isLocale ( $date, true, false )) {
			$locale = $date;
			$date = null;
			$part = null;
		} else if (($part !== null) and ! defined ( $part ) and Zend_Locale::isLocale ( $part, true, false )) {
			$locale = $part;
			$part = null;
		}
		
		$this->setLocale ( $locale );
		if (is_string ( $date ) && ($part === null) && (strlen ( $date ) <= 5)) {
			$part = $date;
			$date = null;
		}
		
		if ($date === null) {
			if ($part === null) {
				$date = time ();
			} else if ($part !== self::TIMESTAMP) {
				$date = self::now ( $locale );
				$date = $date->get ( $part );
			}
		}
		
		if ($date instanceof Zend_TimeSync_Protocol) {
			$date = $date->getInfo ();
			$date = $this->_getTime ( $date ['offset'] );
			$part = null;
		} else if (parent::$_defaultOffset != 0) {
			$date = $this->_getTime ( parent::$_defaultOffset );
		}
		
		// set the timezone and offset for $this
		$zone = @date_default_timezone_get ();
		$this->setTimezone ( $zone );
		
		// try to get timezone from date-string
		if (! is_int ( $date )) {
			$zone = $this->getTimezoneFromString ( $date );
			$this->setTimezone ( $zone );
		}
		
		// set datepart
		if (($part !== null && $part !== self::TIMESTAMP) or (! is_numeric ( $date ))) {
			// switch off dst handling for value setting
			$this->setUnixTimestamp ( $this->getGmtOffset () );
			$this->set ( $date, $part, $this->_locale );
			
			// DST fix
			if (is_array ( $date ) === true) {
				if (! isset ( $date ['hour'] )) {
					$date ['hour'] = 0;
				}
				
				$hour = $this->toString ( 'H', 'iso', true );
				$hour = $date ['hour'] - $hour;
				switch ($hour) {
					case 1 :
					case - 23 :
						$this->addTimestamp ( 3600 );
						break;
					case - 1 :
					case 23 :
						$this->subTimestamp ( 3600 );
						break;
					case 2 :
					case - 22 :
						$this->addTimestamp ( 7200 );
						break;
					case - 2 :
					case 22 :
						$this->subTimestamp ( 7200 );
						break;
				}
			}
		} else {
			$this->setUnixTimestamp ( $date );
		}
	}
	
	/**
	 * Sets class wide options, if no option was given, the actual set options will be returned
	 *
	 * @param  array  $options  Options to set
	 * @throws Zend_Date_Exception
	 * @return Options array if no option was given
	 */
	public static function setOptions(array $options = array()) {
		if (empty ( $options )) {
			return self::$_options;
		}
		
		foreach ( $options as $name => $value ) {
			$name = strtolower ( $name );
			
			if (array_key_exists ( $name, self::$_options )) {
				switch ($name) {
					case 'format_type' :
						if ((strtolower ( $value ) != 'php') && (strtolower ( $value ) != 'iso')) {
							require_once 'Zend/Date/Exception.php';
							throw new Zend_Date_Exception ( "Unknown format type ($value) for dates, only 'iso' and 'php' supported", 0, null, $value );
						}
						break;
					case 'fix_dst' :
						if (! is_bool ( $value )) {
							require_once 'Zend/Date/Exception.php';
							throw new Zend_Date_Exception ( "'fix_dst' has to be boolean", 0, null, $value );
						}
						break;
					case 'extend_month' :
						if (! is_bool ( $value )) {
							require_once 'Zend/Date/Exception.php';
							throw new Zend_Date_Exception ( "'extend_month' has to be boolean", 0, null, $value );
						}
						break;
					case 'cache' :
						if ($value === null) {
							parent::$_cache = null;
						} else {
							if (! $value instanceof Zend_Cache_Core) {
								require_once 'Zend/Date/Exception.php';
								throw new Zend_Date_Exception ( "Instance of Zend_Cache expected" );
							}
							
							parent::$_cache = $value;
							parent::$_cacheTags = Zend_Date_DateObject::_getTagSupportForCache ();
							Zend_Locale_Data::setCache ( $value );
						}
						break;
					case 'timesync' :
						if ($value === null) {
							parent::$_defaultOffset = 0;
						} else {
							if (! $value instanceof Zend_TimeSync_Protocol) {
								require_once 'Zend/Date/Exception.php';
								throw new Zend_Date_Exception ( "Instance of Zend_TimeSync expected" );
							}
							
							$date = $value->getInfo ();
							parent::$_defaultOffset = $date ['offset'];
						}
						break;
				}
				self::$_options [$name] = $value;
			} else {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "Unknown option: $name = $value" );
			}
		}
	}
	
	/**
	 * Returns this object's internal UNIX timestamp (equivalent to Zend_Date::TIMESTAMP).
	 * If the timestamp is too large for integers, then the return value will be a string.
	 * This function does not return the timestamp as an object.
	 * Use clone() or copyPart() instead.
	 *
	 * @return integer|string  UNIX timestamp
	 */
	public function getTimestamp() {
		return $this->getUnixTimestamp ();
	}
	
	/**
	 * Returns the calculated timestamp
	 * HINT: timestamps are always GMT
	 *
	 * @param  string                          $calc    Type of calculation to make
	 * @param  string|integer|array|Zend_Date  $stamp   Timestamp to calculate, when null the actual timestamp is calculated
	 * @return Zend_Date|integer
	 * @throws Zend_Date_Exception
	 */
	private function _timestamp($calc, $stamp) {
		if ($stamp instanceof Zend_Date) {
			// extract timestamp from object
			$stamp = $stamp->getTimestamp ();
		}
		
		if (is_array ( $stamp )) {
			if (isset ( $stamp ['timestamp'] ) === true) {
				$stamp = $stamp ['timestamp'];
			} else {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'no timestamp given in array' );
			}
		}
		
		if ($calc === 'set') {
			$return = $this->setUnixTimestamp ( $stamp );
		} else {
			$return = $this->_calcdetail ( $calc, $stamp, self::TIMESTAMP, null );
		}
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Sets a new timestamp
	 *
	 * @param  integer|string|array|Zend_Date  $timestamp  Timestamp to set
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setTimestamp($timestamp) {
		return $this->_timestamp ( 'set', $timestamp );
	}
	
	/**
	 * Adds a timestamp
	 *
	 * @param  integer|string|array|Zend_Date  $timestamp  Timestamp to add
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addTimestamp($timestamp) {
		return $this->_timestamp ( 'add', $timestamp );
	}
	
	/**
	 * Subtracts a timestamp
	 *
	 * @param  integer|string|array|Zend_Date  $timestamp  Timestamp to sub
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subTimestamp($timestamp) {
		return $this->_timestamp ( 'sub', $timestamp );
	}
	
	/**
	 * Compares two timestamps, returning the difference as integer
	 *
	 * @param  integer|string|array|Zend_Date  $timestamp  Timestamp to compare
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareTimestamp($timestamp) {
		return $this->_timestamp ( 'cmp', $timestamp );
	}
	
	/**
	 * Returns a string representation of the object
	 * Supported format tokens are:
	 * G - era, y - year, Y - ISO year, M - month, w - week of year, D - day of year, d - day of month
	 * E - day of week, e - number of weekday (1-7), h - hour 1-12, H - hour 0-23, m - minute, s - second
	 * A - milliseconds of day, z - timezone, Z - timezone offset, S - fractional second, a - period of day
	 *
	 * Additionally format tokens but non ISO conform are:
	 * SS - day suffix, eee - php number of weekday(0-6), ddd - number of days per month
	 * l - Leap year, B - swatch internet time, I - daylight saving time, X - timezone offset in seconds
	 * r - RFC2822 format, U - unix timestamp
	 *
	 * Not supported ISO tokens are
	 * u - extended year, Q - quarter, q - quarter, L - stand alone month, W - week of month
	 * F - day of week of month, g - modified julian, c - stand alone weekday, k - hour 0-11, K - hour 1-24
	 * v - wall zone
	 *
	 * @param  string              $format  OPTIONAL Rule for formatting output. If null the default date format is used
	 * @param  string              $type    OPTIONAL Type for the format string which overrides the standard setting
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return string
	 */
	public function toString($format = null, $type = null, $locale = null) {
		if (is_object ( $format )) {
			if ($format instanceof Zend_Locale) {
				$locale = $format;
				$format = null;
			} else {
				$format = ( string ) $format;
			}
		}
		
		if (is_object ( $type )) {
			if ($type instanceof Zend_Locale) {
				$locale = $type;
				$type = null;
			} else {
				$type = ( string ) $type;
			}
		}
		
		if (($format !== null) && ! defined ( $format ) && ($format != 'ee') && ($format != 'ss') && ($format != 'GG') && ($format != 'MM') && ($format != 'EE') && ($format != 'TT') && Zend_Locale::isLocale ( $format, null, false )) {
			$locale = $format;
			$format = null;
		}
		
		if (($type !== null) and ($type != 'php') and ($type != 'iso') and Zend_Locale::isLocale ( $type, null, false )) {
			$locale = $type;
			$type = null;
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if ($format === null) {
			$format = Zend_Locale_Format::getDateFormat ( $locale ) . ' ' . Zend_Locale_Format::getTimeFormat ( $locale );
		} else if (((self::$_options ['format_type'] == 'php') && ($type === null)) or ($type == 'php')) {
			$format = Zend_Locale_Format::convertPhpToIsoFormat ( $format );
		}
		
		return $this->date ( $this->_toToken ( $format, $locale ), $this->getUnixTimestamp (), false );
	}
	
	/**
	 * Returns a string representation of the date which is equal with the timestamp
	 *
	 * @return string
	 */
	public function __toString() {
		return $this->toString ( null, $this->_locale );
	}
	
	/**
	 * Returns a integer representation of the object
	 * But returns false when the given part is no value f.e. Month-Name
	 *
	 * @param  string|integer|Zend_Date  $part  OPTIONAL Defines the date or datepart to return as integer
	 * @return integer|false
	 */
	public function toValue($part = null) {
		$result = $this->get ( $part );
		if (is_numeric ( $result )) {
			return intval ( "$result" );
		} else {
			return false;
		}
	}
	
	/**
	 * Returns an array representation of the object
	 *
	 * @return array
	 */
	public function toArray() {
		return array ('day' => $this->toString ( self::DAY_SHORT, 'iso' ), 'month' => $this->toString ( self::MONTH_SHORT, 'iso' ), 'year' => $this->toString ( self::YEAR, 'iso' ), 'hour' => $this->toString ( self::HOUR_SHORT, 'iso' ), 'minute' => $this->toString ( self::MINUTE_SHORT, 'iso' ), 'second' => $this->toString ( self::SECOND_SHORT, 'iso' ), 'timezone' => $this->toString ( self::TIMEZONE, 'iso' ), 'timestamp' => $this->toString ( self::TIMESTAMP, 'iso' ), 'weekday' => $this->toString ( self::WEEKDAY_8601, 'iso' ), 'dayofyear' => $this->toString ( self::DAY_OF_YEAR, 'iso' ), 'week' => $this->toString ( self::WEEK, 'iso' ), 'gmtsecs' => $this->toString ( self::TIMEZONE_SECS, 'iso' ) );
	}
	
	/**
	 * Returns a representation of a date or datepart
	 * This could be for example a localized monthname, the time without date,
	 * the era or only the fractional seconds. There are about 50 different supported date parts.
	 * For a complete list of supported datepart values look into the docu
	 *
	 * @param  string              $part    OPTIONAL Part of the date to return, if null the timestamp is returned
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return string  date or datepart
	 */
	public function get($part = null, $locale = null) {
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if (($part !== null) && ! defined ( $part ) && ($part != 'ee') && ($part != 'ss') && ($part != 'GG') && ($part != 'MM') && ($part != 'EE') && ($part != 'TT') && Zend_Locale::isLocale ( $part, null, false )) {
			$locale = $part;
			$part = null;
		}
		
		if ($part === null) {
			$part = self::TIMESTAMP;
		} else if (self::$_options ['format_type'] == 'php') {
			$part = Zend_Locale_Format::convertPhpToIsoFormat ( $part );
		}
		
		return $this->date ( $this->_toToken ( $part, $locale ), $this->getUnixTimestamp (), false );
	}
	
	/**
	 * Internal method to apply tokens
	 *
	 * @param string $part
	 * @param string $locale
	 * @return string
	 */
	private function _toToken($part, $locale) {
		// get format tokens
		$comment = false;
		$format = '';
		$orig = '';
		for($i = 0; isset ( $part [$i] ); ++ $i) {
			if ($part [$i] == "'") {
				$comment = $comment ? false : true;
				if (isset ( $part [$i + 1] ) && ($part [$i + 1] == "'")) {
					$comment = $comment ? false : true;
					$format .= "\\'";
					++ $i;
				}
				
				$orig = '';
				continue;
			}
			
			if ($comment) {
				$format .= '\\' . $part [$i];
				$orig = '';
			} else {
				$orig .= $part [$i];
				if (! isset ( $part [$i + 1] ) || (isset ( $orig [0] ) && ($orig [0] != $part [$i + 1]))) {
					$format .= $this->_parseIsoToDate ( $orig, $locale );
					$orig = '';
				}
			}
		}
		
		return $format;
	}
	
	/**
	 * Internal parsing method
	 *
	 * @param string $token
	 * @param string $locale
	 * @return string
	 */
	private function _parseIsoToDate($token, $locale) {
		switch ($token) {
			case self::DAY :
				return 'd';
				break;
			
			case self::WEEKDAY_SHORT :
				$weekday = strtolower ( $this->date ( 'D', $this->getUnixTimestamp (), false ) );
				$day = Zend_Locale_Data::getContent ( $locale, 'day', array ('gregorian', 'format', 'wide', $weekday ) );
				return $this->_toComment ( iconv_substr ( $day, 0, 3, 'UTF-8' ) );
				break;
			
			case self::DAY_SHORT :
				return 'j';
				break;
			
			case self::WEEKDAY :
				$weekday = strtolower ( $this->date ( 'D', $this->getUnixTimestamp (), false ) );
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'day', array ('gregorian', 'format', 'wide', $weekday ) ) );
				break;
			
			case self::WEEKDAY_8601 :
				return 'N';
				break;
			
			case 'ee' :
				return $this->_toComment ( str_pad ( $this->date ( 'N', $this->getUnixTimestamp (), false ), 2, '0', STR_PAD_LEFT ) );
				break;
			
			case self::DAY_SUFFIX :
				return 'S';
				break;
			
			case self::WEEKDAY_DIGIT :
				return 'w';
				break;
			
			case self::DAY_OF_YEAR :
				return 'z';
				break;
			
			case 'DDD' :
				return $this->_toComment ( str_pad ( $this->date ( 'z', $this->getUnixTimestamp (), false ), 3, '0', STR_PAD_LEFT ) );
				break;
			
			case 'DD' :
				return $this->_toComment ( str_pad ( $this->date ( 'z', $this->getUnixTimestamp (), false ), 2, '0', STR_PAD_LEFT ) );
				break;
			
			case self::WEEKDAY_NARROW :
			case 'EEEEE' :
				$weekday = strtolower ( $this->date ( 'D', $this->getUnixTimestamp (), false ) );
				$day = Zend_Locale_Data::getContent ( $locale, 'day', array ('gregorian', 'format', 'abbreviated', $weekday ) );
				return $this->_toComment ( iconv_substr ( $day, 0, 1, 'UTF-8' ) );
				break;
			
			case self::WEEKDAY_NAME :
				$weekday = strtolower ( $this->date ( 'D', $this->getUnixTimestamp (), false ) );
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'day', array ('gregorian', 'format', 'abbreviated', $weekday ) ) );
				break;
			
			case 'w' :
				$week = $this->date ( 'W', $this->getUnixTimestamp (), false );
				return $this->_toComment ( ($week [0] == '0') ? $week [1] : $week );
				break;
			
			case self::WEEK :
				return 'W';
				break;
			
			case self::MONTH_NAME :
				$month = $this->date ( 'n', $this->getUnixTimestamp (), false );
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'month', array ('gregorian', 'format', 'wide', $month ) ) );
				break;
			
			case self::MONTH :
				return 'm';
				break;
			
			case self::MONTH_NAME_SHORT :
				$month = $this->date ( 'n', $this->getUnixTimestamp (), false );
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'month', array ('gregorian', 'format', 'abbreviated', $month ) ) );
				break;
			
			case self::MONTH_SHORT :
				return 'n';
				break;
			
			case self::MONTH_DAYS :
				return 't';
				break;
			
			case self::MONTH_NAME_NARROW :
				$month = $this->date ( 'n', $this->getUnixTimestamp (), false );
				$mon = Zend_Locale_Data::getContent ( $locale, 'month', array ('gregorian', 'format', 'abbreviated', $month ) );
				return $this->_toComment ( iconv_substr ( $mon, 0, 1, 'UTF-8' ) );
				break;
			
			case self::LEAPYEAR :
				return 'L';
				break;
			
			case self::YEAR_8601 :
				return 'o';
				break;
			
			case self::YEAR :
				return 'Y';
				break;
			
			case self::YEAR_SHORT :
				return 'y';
				break;
			
			case self::YEAR_SHORT_8601 :
				return $this->_toComment ( substr ( $this->date ( 'o', $this->getUnixTimestamp (), false ), - 2, 2 ) );
				break;
			
			case self::MERIDIEM :
				$am = $this->date ( 'a', $this->getUnixTimestamp (), false );
				if ($am == 'am') {
					return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'am' ) );
				}
				
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'pm' ) );
				break;
			
			case self::SWATCH :
				return 'B';
				break;
			
			case self::HOUR_SHORT_AM :
				return 'g';
				break;
			
			case self::HOUR_SHORT :
				return 'G';
				break;
			
			case self::HOUR_AM :
				return 'h';
				break;
			
			case self::HOUR :
				return 'H';
				break;
			
			case self::MINUTE :
				return $this->_toComment ( str_pad ( $this->date ( 'i', $this->getUnixTimestamp (), false ), 2, '0', STR_PAD_LEFT ) );
				break;
			
			case self::SECOND :
				return $this->_toComment ( str_pad ( $this->date ( 's', $this->getUnixTimestamp (), false ), 2, '0', STR_PAD_LEFT ) );
				break;
			
			case self::MINUTE_SHORT :
				return 'i';
				break;
			
			case self::SECOND_SHORT :
				return 's';
				break;
			
			case self::MILLISECOND :
				return $this->_toComment ( $this->getMilliSecond () );
				break;
			
			case self::TIMEZONE_NAME :
			case 'vvvv' :
				return 'e';
				break;
			
			case self::DAYLIGHT :
				return 'I';
				break;
			
			case self::GMT_DIFF :
			case 'ZZ' :
			case 'ZZZ' :
				return 'O';
				break;
			
			case self::GMT_DIFF_SEP :
				return 'P';
				break;
			
			case self::TIMEZONE :
			case 'v' :
			case 'zz' :
			case 'zzz' :
				return 'T';
				break;
			
			case self::TIMEZONE_SECS :
				return 'Z';
				break;
			
			case self::ISO_8601 :
				return 'c';
				break;
			
			case self::RFC_2822 :
				return 'r';
				break;
			
			case self::TIMESTAMP :
				return 'U';
				break;
			
			case self::ERA :
			case 'GG' :
			case 'GGG' :
				$year = $this->date ( 'Y', $this->getUnixTimestamp (), false );
				if ($year < 0) {
					return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Abbr', '0' ) ) );
				}
				
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Abbr', '1' ) ) );
				break;
			
			case self::ERA_NARROW :
				$year = $this->date ( 'Y', $this->getUnixTimestamp (), false );
				if ($year < 0) {
					return $this->_toComment ( iconv_substr ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Abbr', '0' ) ), 0, 1, 'UTF-8' ) ) . '.';
				}
				
				return $this->_toComment ( iconv_substr ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Abbr', '1' ) ), 0, 1, 'UTF-8' ) ) . '.';
				break;
			
			case self::ERA_NAME :
				$year = $this->date ( 'Y', $this->getUnixTimestamp (), false );
				if ($year < 0) {
					return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Names', '0' ) ) );
				}
				
				return $this->_toComment ( Zend_Locale_Data::getContent ( $locale, 'era', array ('gregorian', 'Names', '1' ) ) );
				break;
			
			case self::DATES :
				return $this->_toToken ( Zend_Locale_Format::getDateFormat ( $locale ), $locale );
				break;
			
			case self::DATE_FULL :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'full' ) ), $locale );
				break;
			
			case self::DATE_LONG :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'long' ) ), $locale );
				break;
			
			case self::DATE_MEDIUM :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'medium' ) ), $locale );
				break;
			
			case self::DATE_SHORT :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'short' ) ), $locale );
				break;
			
			case self::TIMES :
				return $this->_toToken ( Zend_Locale_Format::getTimeFormat ( $locale ), $locale );
				break;
			
			case self::TIME_FULL :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'time', 'full' ), $locale );
				break;
			
			case self::TIME_LONG :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'time', 'long' ), $locale );
				break;
			
			case self::TIME_MEDIUM :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'time', 'medium' ), $locale );
				break;
			
			case self::TIME_SHORT :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'time', 'short' ), $locale );
				break;
			
			case self::DATETIME :
				return $this->_toToken ( Zend_Locale_Format::getDateTimeFormat ( $locale ), $locale );
				break;
			
			case self::DATETIME_FULL :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'full' ) ), $locale );
				break;
			
			case self::DATETIME_LONG :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'long' ) ), $locale );
				break;
			
			case self::DATETIME_MEDIUM :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'medium' ) ), $locale );
				break;
			
			case self::DATETIME_SHORT :
				return $this->_toToken ( Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'short' ) ), $locale );
				break;
			
			case self::ATOM :
				return 'Y\-m\-d\TH\:i\:sP';
				break;
			
			case self::COOKIE :
				return 'l\, d\-M\-y H\:i\:s e';
				break;
			
			case self::RFC_822 :
				return 'D\, d M y H\:i\:s O';
				break;
			
			case self::RFC_850 :
				return 'l\, d\-M\-y H\:i\:s e';
				break;
			
			case self::RFC_1036 :
				return 'D\, d M y H\:i\:s O';
				break;
			
			case self::RFC_1123 :
				return 'D\, d M Y H\:i\:s O';
				break;
			
			case self::RFC_3339 :
				return 'Y\-m\-d\TH\:i\:sP';
				break;
			
			case self::RSS :
				return 'D\, d M Y H\:i\:s O';
				break;
			
			case self::W3C :
				return 'Y\-m\-d\TH\:i\:sP';
				break;
		}
		
		if ($token == '') {
			return '';
		}
		
		switch ($token [0]) {
			case 'y' :
				if ((strlen ( $token ) == 4) && (abs ( $this->getUnixTimestamp () ) <= 0x7FFFFFFF)) {
					return 'Y';
				}
				
				$length = iconv_strlen ( $token, 'UTF-8' );
				return $this->_toComment ( str_pad ( $this->date ( 'Y', $this->getUnixTimestamp (), false ), $length, '0', STR_PAD_LEFT ) );
				break;
			
			case 'Y' :
				if ((strlen ( $token ) == 4) && (abs ( $this->getUnixTimestamp () ) <= 0x7FFFFFFF)) {
					return 'o';
				}
				
				$length = iconv_strlen ( $token, 'UTF-8' );
				return $this->_toComment ( str_pad ( $this->date ( 'o', $this->getUnixTimestamp (), false ), $length, '0', STR_PAD_LEFT ) );
				break;
			
			case 'A' :
				$length = iconv_strlen ( $token, 'UTF-8' );
				$result = substr ( $this->getMilliSecond (), 0, 3 );
				$result += $this->date ( 's', $this->getUnixTimestamp (), false ) * 1000;
				$result += $this->date ( 'i', $this->getUnixTimestamp (), false ) * 60000;
				$result += $this->date ( 'H', $this->getUnixTimestamp (), false ) * 3600000;
				
				return $this->_toComment ( str_pad ( $result, $length, '0', STR_PAD_LEFT ) );
				break;
		}
		
		return $this->_toComment ( $token );
	}
	
	/**
	 * Private function to make a comment of a token
	 *
	 * @param string $token
	 * @return string
	 */
	private function _toComment($token) {
		$token = str_split ( $token );
		$result = '';
		foreach ( $token as $tok ) {
			$result .= '\\' . $tok;
		}
		
		return $result;
	}
	
	/**
	 * Return digit from standard names (english)
	 * Faster implementation than locale aware searching
	 *
	 * @param  string  $name
	 * @return integer  Number of this month
	 * @throws Zend_Date_Exception
	 */
	private function _getDigitFromName($name) {
		switch ($name) {
			case "Jan" :
				return 1;
			
			case "Feb" :
				return 2;
			
			case "Mar" :
				return 3;
			
			case "Apr" :
				return 4;
			
			case "May" :
				return 5;
			
			case "Jun" :
				return 6;
			
			case "Jul" :
				return 7;
			
			case "Aug" :
				return 8;
			
			case "Sep" :
				return 9;
			
			case "Oct" :
				return 10;
			
			case "Nov" :
				return 11;
			
			case "Dec" :
				return 12;
			
			default :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'Month ($name) is not a known month' );
		}
	}
	
	/**
	 * Counts the exact year number
	 * < 70 - 2000 added, >70 < 100 - 1900, others just returned
	 *
	 * @param  integer  $value year number
	 * @return integer  Number of year
	 */
	public static function getFullYear($value) {
		if ($value >= 0) {
			if ($value < 70) {
				$value += 2000;
			} else if ($value < 100) {
				$value += 1900;
			}
		}
		return $value;
	}
	
	/**
	 * Sets the given date as new date or a given datepart as new datepart returning the new datepart
	 * This could be for example a localized dayname, the date without time,
	 * the month or only the seconds. There are about 50 different supported date parts.
	 * For a complete list of supported datepart values look into the docu
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to set
	 * @param  string                          $part    OPTIONAL Part of the date to set, if null the timestamp is set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function set($date, $part = null, $locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$part = Zend_Locale_Format::convertPhpToIsoFormat ( $part );
		}
		
		$zone = $this->getTimezoneFromString ( $date );
		$this->setTimezone ( $zone );
		
		$this->_calculate ( 'set', $date, $part, $locale );
		return $this;
	}
	
	/**
	 * Adds a date or datepart to the existing date, by extracting $part from $date,
	 * and modifying this object by adding that part.  The $part is then extracted from
	 * this object and returned as an integer or numeric string (for large values, or $part's
	 * corresponding to pre-defined formatted date strings).
	 * This could be for example a ISO 8601 date, the hour the monthname or only the minute.
	 * There are about 50 different supported date parts.
	 * For a complete list of supported datepart values look into the docu.
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to add
	 * @param  string                          $part    OPTIONAL Part of the date to add, if null the timestamp is added
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function add($date, $part = self::TIMESTAMP, $locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$part = Zend_Locale_Format::convertPhpToIsoFormat ( $part );
		}
		
		$this->_calculate ( 'add', $date, $part, $locale );
		return $this;
	}
	
	/**
	 * Subtracts a date from another date.
	 * This could be for example a RFC2822 date, the time,
	 * the year or only the timestamp. There are about 50 different supported date parts.
	 * For a complete list of supported datepart values look into the docu
	 * Be aware: Adding -2 Months is not equal to Subtracting 2 Months !!!
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to subtract
	 * @param  string                          $part    OPTIONAL Part of the date to sub, if null the timestamp is subtracted
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function sub($date, $part = self::TIMESTAMP, $locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$part = Zend_Locale_Format::convertPhpToIsoFormat ( $part );
		}
		
		$this->_calculate ( 'sub', $date, $part, $locale );
		return $this;
	}
	
	/**
	 * Compares a date or datepart with the existing one.
	 * Returns -1 if earlier, 0 if equal and 1 if later.
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to compare with the date object
	 * @param  string                          $part    OPTIONAL Part of the date to compare, if null the timestamp is subtracted
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compare($date, $part = self::TIMESTAMP, $locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$part = Zend_Locale_Format::convertPhpToIsoFormat ( $part );
		}
		
		$compare = $this->_calculate ( 'cmp', $date, $part, $locale );
		
		if ($compare > 0) {
			return 1;
		} else if ($compare < 0) {
			return - 1;
		}
		return 0;
	}
	
	/**
	 * Returns a new instance of Zend_Date with the selected part copied.
	 * To make an exact copy, use PHP's clone keyword.
	 * For a complete list of supported date part values look into the docu.
	 * If a date part is copied, all other date parts are set to standard values.
	 * For example: If only YEAR is copied, the returned date object is equal to
	 * 01-01-YEAR 00:00:00 (01-01-1970 00:00:00 is equal to timestamp 0)
	 * If only HOUR is copied, the returned date object is equal to
	 * 01-01-1970 HOUR:00:00 (so $this contains a timestamp equal to a timestamp of 0 plus HOUR).
	 *
	 * @param  string              $part    Part of the date to compare, if null the timestamp is subtracted
	 * @param  string|Zend_Locale  $locale  OPTIONAL New object's locale.  No adjustments to timezone are made.
	 * @return Zend_Date New clone with requested part
	 */
	public function copyPart($part, $locale = null) {
		$clone = clone $this; // copy all instance variables
		$clone->setUnixTimestamp ( 0 ); // except the timestamp
		if ($locale != null) {
			$clone->setLocale ( $locale ); // set an other locale if selected
		}
		$clone->set ( $this, $part );
		return $clone;
	}
	
	/**
	 * Internal function, returns the offset of a given timezone
	 *
	 * @param string $zone
	 * @return integer
	 */
	public function getTimezoneFromString($zone) {
		if (is_array ( $zone )) {
			return $this->getTimezone ();
		}
		
		if ($zone instanceof Zend_Date) {
			return $zone->getTimezone ();
		}
		
		$match = array ();
		preg_match ( '/\dZ$/', $zone, $match );
		if (! empty ( $match )) {
			return "Etc/UTC";
		}
		
		preg_match ( '/([+-]\d{2}):{0,1}\d{2}/', $zone, $match );
		if (! empty ( $match ) and ($match [count ( $match ) - 1] <= 12) and ($match [count ( $match ) - 1] >= - 12)) {
			$zone = "Etc/GMT";
			$zone .= ($match [count ( $match ) - 1] < 0) ? "+" : "-";
			$zone .= ( int ) abs ( $match [count ( $match ) - 1] );
			return $zone;
		}
		
		preg_match ( '/([[:alpha:]\/]{3,30})(?!.*([[:alpha:]\/]{3,30}))/', $zone, $match );
		try {
			if (! empty ( $match ) and (! is_int ( $match [count ( $match ) - 1] ))) {
				$oldzone = $this->getTimezone ();
				$this->setTimezone ( $match [count ( $match ) - 1] );
				$result = $this->getTimezone ();
				$this->setTimezone ( $oldzone );
				if ($result !== $oldzone) {
					return $match [count ( $match ) - 1];
				}
			}
		} catch ( Exception $e ) {
			// fall through
		}
		
		return $this->getTimezone ();
	}
	
	/**
	 * Calculates the date or object
	 *
	 * @param  string                    $calc  Calculation to make
	 * @param  string|integer            $date  Date for calculation
	 * @param  string|integer            $comp  Second date for calculation
	 * @param  boolean|integer           $dst   Use dst correction if option is set
	 * @return integer|string|Zend_Date  new timestamp or Zend_Date depending on calculation
	 */
	private function _assign($calc, $date, $comp = 0, $dst = false) {
		switch ($calc) {
			case 'set' :
				if (! empty ( $comp )) {
					$this->setUnixTimestamp ( call_user_func ( Zend_Locale_Math::$sub, $this->getUnixTimestamp (), $comp ) );
				}
				$this->setUnixTimestamp ( call_user_func ( Zend_Locale_Math::$add, $this->getUnixTimestamp (), $date ) );
				$value = $this->getUnixTimestamp ();
				break;
			case 'add' :
				$this->setUnixTimestamp ( call_user_func ( Zend_Locale_Math::$add, $this->getUnixTimestamp (), $date ) );
				$value = $this->getUnixTimestamp ();
				break;
			case 'sub' :
				$this->setUnixTimestamp ( call_user_func ( Zend_Locale_Math::$sub, $this->getUnixTimestamp (), $date ) );
				$value = $this->getUnixTimestamp ();
				break;
			default :
				// cmp - compare
				return call_user_func ( Zend_Locale_Math::$comp, $comp, $date );
				break;
		}
		
		// dst-correction if 'fix_dst' = true and dst !== false but only for non UTC and non GMT
		if ((self::$_options ['fix_dst'] === true) and ($dst !== false) and ($this->_dst === true)) {
			$hour = $this->toString ( self::HOUR, 'iso' );
			if ($hour != $dst) {
				if (($dst == ($hour + 1)) or ($dst == ($hour - 23))) {
					$value += 3600;
				} else if (($dst == ($hour - 1)) or ($dst == ($hour + 23))) {
					$value -= 3600;
				}
				$this->setUnixTimestamp ( $value );
			}
		}
		return $this->getUnixTimestamp ();
	}
	
	/**
	 * Calculates the date or object
	 *
	 * @param  string                          $calc    Calculation to make, one of: 'add'|'sub'|'cmp'|'copy'|'set'
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to calculate with
	 * @param  string                          $part    Part of the date to calculate, if null the timestamp is used
	 * @param  string|Zend_Locale              $locale  Locale for parsing input
	 * @return integer|string|Zend_Date        new timestamp
	 * @throws Zend_Date_Exception
	 */
	private function _calculate($calc, $date, $part, $locale) {
		if ($date === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $date must be set, null is not allowed' );
		}
		
		if (($part !== null) && (strlen ( $part ) !== 2) && (Zend_Locale::isLocale ( $part, null, false ))) {
			$locale = $part;
			$part = null;
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		$locale = ( string ) $locale;
		
		// Create date parts
		$year = $this->toString ( self::YEAR, 'iso' );
		$month = $this->toString ( self::MONTH_SHORT, 'iso' );
		$day = $this->toString ( self::DAY_SHORT, 'iso' );
		$hour = $this->toString ( self::HOUR_SHORT, 'iso' );
		$minute = $this->toString ( self::MINUTE_SHORT, 'iso' );
		$second = $this->toString ( self::SECOND_SHORT, 'iso' );
		// If object extract value
		if ($date instanceof Zend_Date) {
			$date = $date->toString ( $part, 'iso', $locale );
		}
		
		if (is_array ( $date ) === true) {
			if (empty ( $part ) === false) {
				switch ($part) {
					// Fall through
					case self::DAY :
					case self::DAY_SHORT :
						if (isset ( $date ['day'] ) === true) {
							$date = $date ['day'];
						}
						break;
					// Fall through
					case self::WEEKDAY_SHORT :
					case self::WEEKDAY :
					case self::WEEKDAY_8601 :
					case self::WEEKDAY_DIGIT :
					case self::WEEKDAY_NARROW :
					case self::WEEKDAY_NAME :
						if (isset ( $date ['weekday'] ) === true) {
							$date = $date ['weekday'];
							$part = self::WEEKDAY_DIGIT;
						}
						break;
					case self::DAY_OF_YEAR :
						if (isset ( $date ['day_of_year'] ) === true) {
							$date = $date ['day_of_year'];
						}
						break;
					// Fall through
					case self::MONTH :
					case self::MONTH_SHORT :
					case self::MONTH_NAME :
					case self::MONTH_NAME_SHORT :
					case self::MONTH_NAME_NARROW :
						if (isset ( $date ['month'] ) === true) {
							$date = $date ['month'];
						}
						break;
					// Fall through
					case self::YEAR :
					case self::YEAR_SHORT :
					case self::YEAR_8601 :
					case self::YEAR_SHORT_8601 :
						if (isset ( $date ['year'] ) === true) {
							$date = $date ['year'];
						}
						break;
					// Fall through
					case self::HOUR :
					case self::HOUR_AM :
					case self::HOUR_SHORT :
					case self::HOUR_SHORT_AM :
						if (isset ( $date ['hour'] ) === true) {
							$date = $date ['hour'];
						}
						break;
					// Fall through
					case self::MINUTE :
					case self::MINUTE_SHORT :
						if (isset ( $date ['minute'] ) === true) {
							$date = $date ['minute'];
						}
						break;
					// Fall through
					case self::SECOND :
					case self::SECOND_SHORT :
						if (isset ( $date ['second'] ) === true) {
							$date = $date ['second'];
						}
						break;
					// Fall through
					case self::TIMEZONE :
					case self::TIMEZONE_NAME :
						if (isset ( $date ['timezone'] ) === true) {
							$date = $date ['timezone'];
						}
						break;
					case self::TIMESTAMP :
						if (isset ( $date ['timestamp'] ) === true) {
							$date = $date ['timestamp'];
						}
						break;
					case self::WEEK :
						if (isset ( $date ['week'] ) === true) {
							$date = $date ['week'];
						}
						break;
					case self::TIMEZONE_SECS :
						if (isset ( $date ['gmtsecs'] ) === true) {
							$date = $date ['gmtsecs'];
						}
						break;
					default :
						require_once 'Zend/Date/Exception.php';
						throw new Zend_Date_Exception ( "datepart for part ($part) not found in array" );
						break;
				}
			} else {
				$hours = 0;
				if (isset ( $date ['hour'] ) === true) {
					$hours = $date ['hour'];
				}
				$minutes = 0;
				if (isset ( $date ['minute'] ) === true) {
					$minutes = $date ['minute'];
				}
				$seconds = 0;
				if (isset ( $date ['second'] ) === true) {
					$seconds = $date ['second'];
				}
				$months = 0;
				if (isset ( $date ['month'] ) === true) {
					$months = $date ['month'];
				}
				$days = 0;
				if (isset ( $date ['day'] ) === true) {
					$days = $date ['day'];
				}
				$years = 0;
				if (isset ( $date ['year'] ) === true) {
					$years = $date ['year'];
				}
				return $this->_assign ( $calc, $this->mktime ( $hours, $minutes, $seconds, $months, $days, $years, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), $hour );
			}
		}
		
		// $date as object, part of foreign date as own date
		switch ($part) {
			
			// day formats
			case self::DAY :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + intval ( $date ), 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + intval ( $day ), 1970, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, day expected", 0, null, $date );
				break;
			
			case self::WEEKDAY_SHORT :
				$daylist = Zend_Locale_Data::getList ( $locale, 'day' );
				$weekday = ( int ) $this->toString ( self::WEEKDAY_DIGIT, 'iso', $locale );
				$cnt = 0;
				
				foreach ( $daylist as $key => $value ) {
					if (strtoupper ( iconv_substr ( $value, 0, 3, 'UTF-8' ) ) == strtoupper ( $date )) {
						$found = $cnt;
						break;
					}
					++ $cnt;
				}
				
				// Weekday found
				if ($cnt < 7) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + $found, 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			case self::DAY_SHORT :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + intval ( $date ), 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + intval ( $day ), 1970, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, day expected", 0, null, $date );
				break;
			
			case self::WEEKDAY :
				$daylist = Zend_Locale_Data::getList ( $locale, 'day' );
				$weekday = ( int ) $this->toString ( self::WEEKDAY_DIGIT, 'iso', $locale );
				$cnt = 0;
				
				foreach ( $daylist as $key => $value ) {
					if (strtoupper ( $value ) == strtoupper ( $date )) {
						$found = $cnt;
						break;
					}
					++ $cnt;
				}
				
				// Weekday found
				if ($cnt < 7) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + $found, 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			case self::WEEKDAY_8601 :
				$weekday = ( int ) $this->toString ( self::WEEKDAY_8601, 'iso', $locale );
				if ((intval ( $date ) > 0) and (intval ( $date ) < 8)) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + intval ( $date ), 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			case self::DAY_SUFFIX :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'day suffix not supported', 0, null, $date );
				break;
			
			case self::WEEKDAY_DIGIT :
				$weekday = ( int ) $this->toString ( self::WEEKDAY_DIGIT, 'iso', $locale );
				if (is_numeric ( $date ) and (intval ( $date ) >= 0) and (intval ( $date ) < 7)) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + $date, 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			case self::DAY_OF_YEAR :
				if (is_numeric ( $date )) {
					if (($calc == 'add') || ($calc == 'sub')) {
						$year = 1970;
						++ $date;
						++ $day;
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, $date, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, day expected", 0, null, $date );
				break;
			
			case self::WEEKDAY_NARROW :
				$daylist = Zend_Locale_Data::getList ( $locale, 'day', array ('gregorian', 'format', 'abbreviated' ) );
				$weekday = ( int ) $this->toString ( self::WEEKDAY_DIGIT, 'iso', $locale );
				$cnt = 0;
				foreach ( $daylist as $key => $value ) {
					if (strtoupper ( iconv_substr ( $value, 0, 1, 'UTF-8' ) ) == strtoupper ( $date )) {
						$found = $cnt;
						break;
					}
					++ $cnt;
				}
				
				// Weekday found
				if ($cnt < 7) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + $found, 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			case self::WEEKDAY_NAME :
				$daylist = Zend_Locale_Data::getList ( $locale, 'day', array ('gregorian', 'format', 'abbreviated' ) );
				$weekday = ( int ) $this->toString ( self::WEEKDAY_DIGIT, 'iso', $locale );
				$cnt = 0;
				foreach ( $daylist as $key => $value ) {
					if (strtoupper ( $value ) == strtoupper ( $date )) {
						$found = $cnt;
						break;
					}
					++ $cnt;
				}
				
				// Weekday found
				if ($cnt < 7) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1, 1 + $found, 1970, true ), $this->mktime ( 0, 0, 0, 1, 1 + $weekday, 1970, true ), $hour );
				}
				
				// Weekday not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, weekday expected", 0, null, $date );
				break;
			
			// week formats
			case self::WEEK :
				if (is_numeric ( $date )) {
					$week = ( int ) $this->toString ( self::WEEK, 'iso', $locale );
					return $this->_assign ( $calc, parent::mktime ( 0, 0, 0, 1, 1 + ($date * 7), 1970, true ), parent::mktime ( 0, 0, 0, 1, 1 + ($week * 7), 1970, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, week expected", 0, null, $date );
				break;
			
			// month formats
			case self::MONTH_NAME :
				$monthlist = Zend_Locale_Data::getList ( $locale, 'month' );
				$cnt = 0;
				foreach ( $monthlist as $key => $value ) {
					if (strtoupper ( $value ) == strtoupper ( $date )) {
						$found = $key;
						break;
					}
					++ $cnt;
				}
				$date = array_search ( $date, $monthlist );
				
				// Monthname found
				if ($cnt < 12) {
					$fixday = 0;
					if ($calc == 'add') {
						$date += $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] == false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					} else if ($calc == 'sub') {
						$date = $month - $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] == false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $date, $day + $fixday, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				// Monthname not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, month expected", 0, null, $date );
				break;
			
			case self::MONTH :
				if (is_numeric ( $date )) {
					$fixday = 0;
					if ($calc == 'add') {
						$date += $month;
						$calc = 'set';
						if (self::$_options ['extend_month'] == false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					} else if ($calc == 'sub') {
						$date = $month - $date;
						$calc = 'set';
						if (self::$_options ['extend_month'] == false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $date, $day + $fixday, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, month expected", 0, null, $date );
				break;
			
			case self::MONTH_NAME_SHORT :
				$monthlist = Zend_Locale_Data::getList ( $locale, 'month', array ('gregorian', 'format', 'abbreviated' ) );
				$cnt = 0;
				foreach ( $monthlist as $key => $value ) {
					if (strtoupper ( $value ) == strtoupper ( $date )) {
						$found = $key;
						break;
					}
					++ $cnt;
				}
				$date = array_search ( $date, $monthlist );
				
				// Monthname found
				if ($cnt < 12) {
					$fixday = 0;
					if ($calc == 'add') {
						$date += $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					} else if ($calc == 'sub') {
						$date = $month - $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $date, $day + $fixday, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				// Monthname not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, month expected", 0, null, $date );
				break;
			
			case self::MONTH_SHORT :
				if (is_numeric ( $date ) === true) {
					$fixday = 0;
					if ($calc === 'add') {
						$date += $month;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					} else if ($calc === 'sub') {
						$date = $month - $date;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $date, $day + $fixday, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, month expected", 0, null, $date );
				break;
			
			case self::MONTH_DAYS :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'month days not supported', 0, null, $date );
				break;
			
			case self::MONTH_NAME_NARROW :
				$monthlist = Zend_Locale_Data::getList ( $locale, 'month', array ('gregorian', 'stand-alone', 'narrow' ) );
				$cnt = 0;
				foreach ( $monthlist as $key => $value ) {
					if (strtoupper ( $value ) === strtoupper ( $date )) {
						$found = $key;
						break;
					}
					++ $cnt;
				}
				$date = array_search ( $date, $monthlist );
				
				// Monthname found
				if ($cnt < 12) {
					$fixday = 0;
					if ($calc === 'add') {
						$date += $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					} else if ($calc === 'sub') {
						$date = $month - $found;
						$calc = 'set';
						if (self::$_options ['extend_month'] === false) {
							$parts = $this->getDateParts ( $this->mktime ( $hour, $minute, $second, $date, $day, $year, false ) );
							if ($parts ['mday'] != $day) {
								$fixday = ($parts ['mday'] < $day) ? - $parts ['mday'] : ($parts ['mday'] - $day);
							}
						}
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $date, $day + $fixday, $year, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), $hour );
				}
				
				// Monthname not found
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, month expected", 0, null, $date );
				break;
			
			// year formats
			case self::LEAPYEAR :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'leap year not supported', 0, null, $date );
				break;
			
			case self::YEAR_8601 :
				if (is_numeric ( $date )) {
					if ($calc === 'add') {
						$date += $year;
						$calc = 'set';
					} else if ($calc === 'sub') {
						$date = $year - $date;
						$calc = 'set';
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $month, $day, intval ( $date ), true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, year expected", 0, null, $date );
				break;
			
			case self::YEAR :
				if (is_numeric ( $date )) {
					if ($calc === 'add') {
						$date += $year;
						$calc = 'set';
					} else if ($calc === 'sub') {
						$date = $year - $date;
						$calc = 'set';
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $month, $day, intval ( $date ), true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, year expected", 0, null, $date );
				break;
			
			case self::YEAR_SHORT :
				if (is_numeric ( $date )) {
					$date = intval ( $date );
					if (($calc == 'set') || ($calc == 'cmp')) {
						$date = self::getFullYear ( $date );
					}
					if ($calc === 'add') {
						$date += $year;
						$calc = 'set';
					} else if ($calc === 'sub') {
						$date = $year - $date;
						$calc = 'set';
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $month, $day, $date, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, year expected", 0, null, $date );
				break;
			
			case self::YEAR_SHORT_8601 :
				if (is_numeric ( $date )) {
					$date = intval ( $date );
					if (($calc === 'set') || ($calc === 'cmp')) {
						$date = self::getFullYear ( $date );
					}
					if ($calc === 'add') {
						$date += $year;
						$calc = 'set';
					} else if ($calc === 'sub') {
						$date = $year - $date;
						$calc = 'set';
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, $month, $day, $date, true ), $this->mktime ( 0, 0, 0, $month, $day, $year, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, year expected", 0, null, $date );
				break;
			
			// time formats
			case self::MERIDIEM :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'meridiem not supported', 0, null, $date );
				break;
			
			case self::SWATCH :
				if (is_numeric ( $date )) {
					$rest = intval ( $date );
					$hours = floor ( $rest * 24 / 1000 );
					$rest = $rest - ($hours * 1000 / 24);
					$minutes = floor ( $rest * 1440 / 1000 );
					$rest = $rest - ($minutes * 1000 / 1440);
					$seconds = floor ( $rest * 86400 / 1000 );
					return $this->_assign ( $calc, $this->mktime ( $hours, $minutes, $seconds, 1, 1, 1970, true ), $this->mktime ( $hour, $minute, $second, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, swatchstamp expected", 0, null, $date );
				break;
			
			case self::HOUR_SHORT_AM :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( intval ( $date ), 0, 0, 1, 1, 1970, true ), $this->mktime ( $hour, 0, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, hour expected", 0, null, $date );
				break;
			
			case self::HOUR_SHORT :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( intval ( $date ), 0, 0, 1, 1, 1970, true ), $this->mktime ( $hour, 0, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, hour expected", 0, null, $date );
				break;
			
			case self::HOUR_AM :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( intval ( $date ), 0, 0, 1, 1, 1970, true ), $this->mktime ( $hour, 0, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, hour expected", 0, null, $date );
				break;
			
			case self::HOUR :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( intval ( $date ), 0, 0, 1, 1, 1970, true ), $this->mktime ( $hour, 0, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, hour expected", 0, null, $date );
				break;
			
			case self::MINUTE :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, intval ( $date ), 0, 1, 1, 1970, true ), $this->mktime ( 0, $minute, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, minute expected", 0, null, $date );
				break;
			
			case self::SECOND :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, intval ( $date ), 1, 1, 1970, true ), $this->mktime ( 0, 0, $second, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, second expected", 0, null, $date );
				break;
			
			case self::MILLISECOND :
				if (is_numeric ( $date )) {
					switch ($calc) {
						case 'set' :
							return $this->setMillisecond ( $date );
							break;
						case 'add' :
							return $this->addMillisecond ( $date );
							break;
						case 'sub' :
							return $this->subMillisecond ( $date );
							break;
					}
					
					return $this->compareMillisecond ( $date );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, milliseconds expected", 0, null, $date );
				break;
			
			case self::MINUTE_SHORT :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, intval ( $date ), 0, 1, 1, 1970, true ), $this->mktime ( 0, $minute, 0, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, minute expected", 0, null, $date );
				break;
			
			case self::SECOND_SHORT :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $this->mktime ( 0, 0, intval ( $date ), 1, 1, 1970, true ), $this->mktime ( 0, 0, $second, 1, 1, 1970, true ), false );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, second expected", 0, null, $date );
				break;
			
			// timezone formats
			// break intentionally omitted
			case self::TIMEZONE_NAME :
			case self::TIMEZONE :
			case self::TIMEZONE_SECS :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'timezone not supported', 0, null, $date );
				break;
			
			case self::DAYLIGHT :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'daylight not supported', 0, null, $date );
				break;
			
			case self::GMT_DIFF :
			case self::GMT_DIFF_SEP :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'gmtdiff not supported', 0, null, $date );
				break;
			
			// date strings
			case self::ISO_8601 :
				// (-)YYYY-MM-dd
				preg_match ( '/^(-{0,1}\d{4})-(\d{2})-(\d{2})/', $date, $datematch );
				// (-)YY-MM-dd
				if (empty ( $datematch )) {
					preg_match ( '/^(-{0,1}\d{2})-(\d{2})-(\d{2})/', $date, $datematch );
				}
				// (-)YYYYMMdd
				if (empty ( $datematch )) {
					preg_match ( '/^(-{0,1}\d{4})(\d{2})(\d{2})/', $date, $datematch );
				}
				// (-)YYMMdd
				if (empty ( $datematch )) {
					preg_match ( '/^(-{0,1}\d{2})(\d{2})(\d{2})/', $date, $datematch );
				}
				$tmpdate = $date;
				if (! empty ( $datematch )) {
					$dateMatchCharCount = iconv_strlen ( $datematch [0], 'UTF-8' );
					$tmpdate = iconv_substr ( $date, $dateMatchCharCount, iconv_strlen ( $date, 'UTF-8' ) - $dateMatchCharCount, 'UTF-8' );
				}
				// (T)hh:mm:ss
				preg_match ( '/[T,\s]{0,1}(\d{2}):(\d{2}):(\d{2})/', $tmpdate, $timematch );
				if (empty ( $timematch )) {
					preg_match ( '/[T,\s]{0,1}(\d{2})(\d{2})(\d{2})/', $tmpdate, $timematch );
				}
				if (empty ( $datematch ) and empty ( $timematch )) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "unsupported ISO8601 format ($date)", 0, null, $date );
				}
				if (! empty ( $timematch )) {
					$timeMatchCharCount = iconv_strlen ( $timematch [0], 'UTF-8' );
					$tmpdate = iconv_substr ( $tmpdate, $timeMatchCharCount, iconv_strlen ( $tmpdate, 'UTF-8' ) - $timeMatchCharCount, 'UTF-8' );
				}
				if (empty ( $datematch )) {
					$datematch [1] = 1970;
					$datematch [2] = 1;
					$datematch [3] = 1;
				} else if (iconv_strlen ( $datematch [1], 'UTF-8' ) == 2) {
					$datematch [1] = self::getFullYear ( $datematch [1] );
				}
				if (empty ( $timematch )) {
					$timematch [1] = 0;
					$timematch [2] = 0;
					$timematch [3] = 0;
				}
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $datematch [2];
					-- $month;
					-- $datematch [3];
					-- $day;
					$datematch [1] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $timematch [1], $timematch [2], $timematch [3], 1 + $datematch [2], 1 + $datematch [3], 1970 + $datematch [1], false ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, false ), false );
				break;
			
			case self::RFC_2822 :
				$result = preg_match ( '/^\w{3},\s(\d{1,2})\s(\w{3})\s(\d{4})\s' . '(\d{2}):(\d{2}):{0,1}(\d{0,2})\s([+-]' . '{1}\d{4}|\w{1,20})$/', $date, $match );
				
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "no RFC 2822 format ($date)", 0, null, $date );
				}
				
				$months = $this->_getDigitFromName ( $match [2] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], false ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, false ), false );
				break;
			
			case self::TIMESTAMP :
				if (is_numeric ( $date )) {
					return $this->_assign ( $calc, $date, $this->getUnixTimestamp () );
				}
				
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "invalid date ($date) operand, timestamp expected", 0, null, $date );
				break;
			
			// additional formats
			// break intentionally omitted
			case self::ERA :
			case self::ERA_NAME :
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( 'era not supported', 0, null, $date );
				break;
			
			case self::DATES :
				try {
					$parsed = Zend_Locale_Format::getDate ( $date, array ('locale' => $locale, 'format_type' => 'iso', 'fix_date' => true ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( 0, 0, 0, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATE_FULL :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'full' ) );
					$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( 0, 0, 0, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATE_LONG :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'long' ) );
					$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( 0, 0, 0, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATE_MEDIUM :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'medium' ) );
					$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( 0, 0, 0, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATE_SHORT :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'short' ) );
					$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					$parsed ['year'] = self::getFullYear ( $parsed ['year'] );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( 0, 0, 0, 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( 0, 0, 0, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::TIMES :
				try {
					if ($calc != 'set') {
						$month = 1;
						$day = 1;
						$year = 1970;
					}
					$parsed = Zend_Locale_Format::getTime ( $date, array ('locale' => $locale, 'format_type' => 'iso', 'fix_date' => true ) );
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $month, $day, $year, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), false );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::TIME_FULL :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'full' ) );
					$parsed = Zend_Locale_Format::getTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					if ($calc != 'set') {
						$month = 1;
						$day = 1;
						$year = 1970;
					}
					
					if (! isset ( $parsed ['second'] )) {
						$parsed ['second'] = 0;
					}
					
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $month, $day, $year, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), false );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::TIME_LONG :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'long' ) );
					$parsed = Zend_Locale_Format::getTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					if ($calc != 'set') {
						$month = 1;
						$day = 1;
						$year = 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $month, $day, $year, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), false );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::TIME_MEDIUM :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'medium' ) );
					$parsed = Zend_Locale_Format::getTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					if ($calc != 'set') {
						$month = 1;
						$day = 1;
						$year = 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $month, $day, $year, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), false );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::TIME_SHORT :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'short' ) );
					$parsed = Zend_Locale_Format::getTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					if ($calc != 'set') {
						$month = 1;
						$day = 1;
						$year = 1970;
					}
					
					if (! isset ( $parsed ['second'] )) {
						$parsed ['second'] = 0;
					}
					
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $month, $day, $year, true ), $this->mktime ( $hour, $minute, $second, $month, $day, $year, true ), false );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATETIME :
				try {
					$parsed = Zend_Locale_Format::getDateTime ( $date, array ('locale' => $locale, 'format_type' => 'iso', 'fix_date' => true ) );
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATETIME_FULL :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'full' ) );
					$parsed = Zend_Locale_Format::getDateTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					
					if (! isset ( $parsed ['second'] )) {
						$parsed ['second'] = 0;
					}
					
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATETIME_LONG :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'long' ) );
					$parsed = Zend_Locale_Format::getDateTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATETIME_MEDIUM :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'medium' ) );
					$parsed = Zend_Locale_Format::getDateTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			case self::DATETIME_SHORT :
				try {
					$format = Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'short' ) );
					$parsed = Zend_Locale_Format::getDateTime ( $date, array ('date_format' => $format, 'format_type' => 'iso', 'locale' => $locale ) );
					
					$parsed ['year'] = self::getFullYear ( $parsed ['year'] );
					
					if (($calc == 'set') || ($calc == 'cmp')) {
						-- $parsed ['month'];
						-- $month;
						-- $parsed ['day'];
						-- $day;
						$parsed ['year'] -= 1970;
						$year -= 1970;
					}
					
					if (! isset ( $parsed ['second'] )) {
						$parsed ['second'] = 0;
					}
					
					return $this->_assign ( $calc, $this->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], 1 + $parsed ['month'], 1 + $parsed ['day'], 1970 + $parsed ['year'], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), $hour );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
				}
				break;
			
			// ATOM and RFC_3339 are identical
			case self::ATOM :
			case self::RFC_3339 :
				$result = preg_match ( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})\d{0,4}([+-]{1}\d{2}:\d{2}|Z)$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, ATOM format expected", 0, null, $date );
				}
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $match [2];
					-- $month;
					-- $match [3];
					-- $day;
					$match [1] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $match [2], 1 + $match [3], 1970 + $match [1], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			case self::COOKIE :
				$result = preg_match ( "/^\w{6,9},\s(\d{2})-(\w{3})-(\d{2})\s(\d{2}):(\d{2}):(\d{2})\s.{3,20}$/", $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, COOKIE format expected", 0, null, $date );
				}
				$matchStartPos = iconv_strpos ( $match [0], ' ', 0, 'UTF-8' ) + 1;
				$match [0] = iconv_substr ( $match [0], $matchStartPos, iconv_strlen ( $match [0], 'UTF-8' ) - $matchStartPos, 'UTF-8' );
				
				$months = $this->_getDigitFromName ( $match [2] );
				$match [3] = self::getFullYear ( $match [3] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			case self::RFC_822 :
			case self::RFC_1036 :
				// new RFC 822 format, identical to RFC 1036 standard
				$result = preg_match ( '/^\w{0,3},{0,1}\s{0,1}(\d{1,2})\s(\w{3})\s(\d{2})\s(\d{2}):(\d{2}):{0,1}(\d{0,2})\s([+-]{1}\d{4}|\w{1,20})$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, RFC 822 date format expected", 0, null, $date );
				}
				
				$months = $this->_getDigitFromName ( $match [2] );
				$match [3] = self::getFullYear ( $match [3] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], false ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, false ), false );
				break;
			
			case self::RFC_850 :
				$result = preg_match ( '/^\w{6,9},\s(\d{2})-(\w{3})-(\d{2})\s(\d{2}):(\d{2}):(\d{2})\s.{3,21}$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, RFC 850 date format expected", 0, null, $date );
				}
				
				$months = $this->_getDigitFromName ( $match [2] );
				$match [3] = self::getFullYear ( $match [3] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			case self::RFC_1123 :
				$result = preg_match ( '/^\w{0,3},{0,1}\s{0,1}(\d{1,2})\s(\w{3})\s(\d{2,4})\s(\d{2}):(\d{2}):{0,1}(\d{0,2})\s([+-]{1}\d{4}|\w{1,20})$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, RFC 1123 date format expected", 0, null, $date );
				}
				
				$months = $this->_getDigitFromName ( $match [2] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			case self::RSS :
				$result = preg_match ( '/^\w{3},\s(\d{2})\s(\w{3})\s(\d{2,4})\s(\d{1,2}):(\d{2}):(\d{2})\s.{1,21}$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, RSS date format expected", 0, null, $date );
				}
				
				$months = $this->_getDigitFromName ( $match [2] );
				$match [3] = self::getFullYear ( $match [3] );
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $months;
					-- $month;
					-- $match [1];
					-- $day;
					$match [3] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $months, 1 + $match [1], 1970 + $match [3], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			case self::W3C :
				$result = preg_match ( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})[+-]{1}\d{2}:\d{2}$/', $date, $match );
				if (! $result) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "invalid date ($date) operand, W3C date format expected", 0, null, $date );
				}
				
				if (($calc == 'set') || ($calc == 'cmp')) {
					-- $match [2];
					-- $month;
					-- $match [3];
					-- $day;
					$match [1] -= 1970;
					$year -= 1970;
				}
				return $this->_assign ( $calc, $this->mktime ( $match [4], $match [5], $match [6], 1 + $match [2], 1 + $match [3], 1970 + $match [1], true ), $this->mktime ( $hour, $minute, $second, 1 + $month, 1 + $day, 1970 + $year, true ), false );
				break;
			
			default :
				if (! is_numeric ( $date ) || ! empty ( $part )) {
					try {
						if (empty ( $part )) {
							$part = Zend_Locale_Format::getDateFormat ( $locale ) . " ";
							$part .= Zend_Locale_Format::getTimeFormat ( $locale );
						}
						
						$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $part, 'locale' => $locale, 'fix_date' => true, 'format_type' => 'iso' ) );
						if ((strpos ( strtoupper ( $part ), 'YY' ) !== false) and (strpos ( strtoupper ( $part ), 'YYYY' ) === false)) {
							$parsed ['year'] = self::getFullYear ( $parsed ['year'] );
						}
						
						if (($calc == 'set') || ($calc == 'cmp')) {
							if (isset ( $parsed ['month'] )) {
								-- $parsed ['month'];
							} else {
								$parsed ['month'] = 0;
							}
							
							if (isset ( $parsed ['day'] )) {
								-- $parsed ['day'];
							} else {
								$parsed ['day'] = 0;
							}
							
							if (isset ( $parsed ['year'] )) {
								$parsed ['year'] -= 1970;
							} else {
								$parsed ['year'] = 0;
							}
						}
						
						return $this->_assign ( $calc, $this->mktime ( isset ( $parsed ['hour'] ) ? $parsed ['hour'] : 0, isset ( $parsed ['minute'] ) ? $parsed ['minute'] : 0, isset ( $parsed ['second'] ) ? $parsed ['second'] : 0, isset ( $parsed ['month'] ) ? (1 + $parsed ['month']) : 1, isset ( $parsed ['day'] ) ? (1 + $parsed ['day']) : 1, isset ( $parsed ['year'] ) ? (1970 + $parsed ['year']) : 1970, false ), $this->getUnixTimestamp (), false );
					} catch ( Zend_Locale_Exception $e ) {
						if (! is_numeric ( $date )) {
							require_once 'Zend/Date/Exception.php';
							throw new Zend_Date_Exception ( $e->getMessage (), 0, $e, $date );
						}
					}
				}
				
				return $this->_assign ( $calc, $date, $this->getUnixTimestamp (), false );
				break;
		}
	}
	
	/**
	 * Returns true when both date objects or date parts are equal.
	 * For example:
	 * 15.May.2000 <-> 15.June.2000 Equals only for Day or Year... all other will return false
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to equal with
	 * @param  string                          $part    OPTIONAL Part of the date to compare, if null the timestamp is used
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return boolean
	 * @throws Zend_Date_Exception
	 */
	public function equals($date, $part = self::TIMESTAMP, $locale = null) {
		$result = $this->compare ( $date, $part, $locale );
		
		if ($result == 0) {
			return true;
		}
		
		return false;
	}
	
	/**
	 * Returns if the given date or datepart is earlier
	 * For example:
	 * 15.May.2000 <-> 13.June.1999 will return true for day, year and date, but not for month
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to compare with
	 * @param  string                          $part    OPTIONAL Part of the date to compare, if null the timestamp is used
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return boolean
	 * @throws Zend_Date_Exception
	 */
	public function isEarlier($date, $part = null, $locale = null) {
		$result = $this->compare ( $date, $part, $locale );
		
		if ($result == - 1) {
			return true;
		}
		
		return false;
	}
	
	/**
	 * Returns if the given date or datepart is later
	 * For example:
	 * 15.May.2000 <-> 13.June.1999 will return true for month but false for day, year and date
	 * Returns if the given date is later
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date or datepart to compare with
	 * @param  string                          $part    OPTIONAL Part of the date to compare, if null the timestamp is used
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return boolean
	 * @throws Zend_Date_Exception
	 */
	public function isLater($date, $part = null, $locale = null) {
		$result = $this->compare ( $date, $part, $locale );
		
		if ($result == 1) {
			return true;
		}
		
		return false;
	}
	
	/**
	 * Returns only the time of the date as new Zend_Date object
	 * For example:
	 * 15.May.2000 10:11:23 will return a dateobject equal to 01.Jan.1970 10:11:23
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getTime($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'H:i:s';
		} else {
			$format = self::TIME_MEDIUM;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Returns the calculated time
	 *
	 * @param  string                    $calc    Calculation to make
	 * @param  string|integer|array|Zend_Date  $time    Time to calculate with, if null the actual time is taken
	 * @param  string                          $format  Timeformat for parsing input
	 * @param  string|Zend_Locale              $locale  Locale for parsing input
	 * @return integer|Zend_Date  new time
	 * @throws Zend_Date_Exception
	 */
	private function _time($calc, $time, $format, $locale) {
		if ($time === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $time must be set, null is not allowed' );
		}
		
		if ($time instanceof Zend_Date) {
			// extract time from object
			$time = $time->toString ( 'HH:mm:ss', 'iso' );
		} else {
			if (is_array ( $time )) {
				if ((isset ( $time ['hour'] ) === true) or (isset ( $time ['minute'] ) === true) or (isset ( $time ['second'] ) === true)) {
					$parsed = $time;
				} else {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "no hour, minute or second given in array" );
				}
			} else {
				if (self::$_options ['format_type'] == 'php') {
					$format = Zend_Locale_Format::convertPhpToIsoFormat ( $format );
				}
				try {
					if ($locale === null) {
						$locale = $this->getLocale ();
					}
					
					$parsed = Zend_Locale_Format::getTime ( $time, array ('date_format' => $format, 'locale' => $locale, 'format_type' => 'iso' ) );
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e );
				}
			}
			
			if (! array_key_exists ( 'hour', $parsed )) {
				$parsed ['hour'] = 0;
			}
			
			if (! array_key_exists ( 'minute', $parsed )) {
				$parsed ['minute'] = 0;
			}
			
			if (! array_key_exists ( 'second', $parsed )) {
				$parsed ['second'] = 0;
			}
			
			$time = str_pad ( $parsed ['hour'], 2, '0', STR_PAD_LEFT ) . ":";
			$time .= str_pad ( $parsed ['minute'], 2, '0', STR_PAD_LEFT ) . ":";
			$time .= str_pad ( $parsed ['second'], 2, '0', STR_PAD_LEFT );
		}
		
		$return = $this->_calcdetail ( $calc, $time, self::TIMES, 'de' );
		if ($calc != 'cmp') {
			return $this;
		}
		
		return $return;
	}
	
	/**
	 * Sets a new time for the date object. Format defines how to parse the time string.
	 * Also a complete date can be given, but only the time is used for setting.
	 * For example: dd.MMMM.yyTHH:mm' and 'ss sec'-> 10.May.07T25:11 and 44 sec => 1h11min44sec + 1 day
	 * Returned is the new date object and the existing date is left as it was before
	 *
	 * @param  string|integer|array|Zend_Date  $time    Time to set
	 * @param  string                          $format  OPTIONAL Timeformat for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setTime($time, $format = null, $locale = null) {
		return $this->_time ( 'set', $time, $format, $locale );
	}
	
	/**
	 * Adds a time to the existing date. Format defines how to parse the time string.
	 * If only parts are given the other parts are set to 0.
	 * If no format is given, the standardformat of this locale is used.
	 * For example: HH:mm:ss -> 10 -> +10 hours
	 *
	 * @param  string|integer|array|Zend_Date  $time    Time to add
	 * @param  string                          $format  OPTIONAL Timeformat for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addTime($time, $format = null, $locale = null) {
		return $this->_time ( 'add', $time, $format, $locale );
	}
	
	/**
	 * Subtracts a time from the existing date. Format defines how to parse the time string.
	 * If only parts are given the other parts are set to 0.
	 * If no format is given, the standardformat of this locale is used.
	 * For example: HH:mm:ss -> 10 -> -10 hours
	 *
	 * @param  string|integer|array|Zend_Date  $time    Time to sub
	 * @param  string                          $format  OPTIONAL Timeformat for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid inteface
	 * @throws Zend_Date_Exception
	 */
	public function subTime($time, $format = null, $locale = null) {
		return $this->_time ( 'sub', $time, $format, $locale );
	}
	
	/**
	 * Compares the time from the existing date. Format defines how to parse the time string.
	 * If only parts are given the other parts are set to default.
	 * If no format us given, the standardformat of this locale is used.
	 * For example: HH:mm:ss -> 10 -> 10 hours
	 *
	 * @param  string|integer|array|Zend_Date  $time    Time to compare
	 * @param  string                          $format  OPTIONAL Timeformat for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareTime($time, $format = null, $locale = null) {
		return $this->_time ( 'cmp', $time, $format, $locale );
	}
	
	/**
	 * Returns a clone of $this, with the time part set to 00:00:00.
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getDate($locale = null) {
		$orig = self::$_options ['format_type'];
		if (self::$_options ['format_type'] == 'php') {
			self::$_options ['format_type'] = 'iso';
		}
		
		$date = $this->copyPart ( self::DATE_MEDIUM, $locale );
		$date->addTimestamp ( $this->getGmtOffset () );
		self::$_options ['format_type'] = $orig;
		
		return $date;
	}
	
	/**
	 * Returns the calculated date
	 *
	 * @param  string                          $calc    Calculation to make
	 * @param  string|integer|array|Zend_Date  $date    Date to calculate with, if null the actual date is taken
	 * @param  string                          $format  Date format for parsing
	 * @param  string|Zend_Locale              $locale  Locale for parsing input
	 * @return integer|Zend_Date  new date
	 * @throws Zend_Date_Exception
	 */
	private function _date($calc, $date, $format, $locale) {
		if ($date === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $date must be set, null is not allowed' );
		}
		
		if ($date instanceof Zend_Date) {
			// extract date from object
			$date = $date->toString ( 'd.M.y', 'iso' );
		} else {
			if (is_array ( $date )) {
				if ((isset ( $date ['year'] ) === true) or (isset ( $date ['month'] ) === true) or (isset ( $date ['day'] ) === true)) {
					$parsed = $date;
				} else {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "no day,month or year given in array" );
				}
			} else {
				if ((self::$_options ['format_type'] == 'php') && ! defined ( $format )) {
					$format = Zend_Locale_Format::convertPhpToIsoFormat ( $format );
				}
				try {
					if ($locale === null) {
						$locale = $this->getLocale ();
					}
					
					$parsed = Zend_Locale_Format::getDate ( $date, array ('date_format' => $format, 'locale' => $locale, 'format_type' => 'iso' ) );
					if ((strpos ( strtoupper ( $format ), 'YY' ) !== false) and (strpos ( strtoupper ( $format ), 'YYYY' ) === false)) {
						$parsed ['year'] = self::getFullYear ( $parsed ['year'] );
					}
				} catch ( Zend_Locale_Exception $e ) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( $e->getMessage (), 0, $e );
				}
			}
			
			if (! array_key_exists ( 'day', $parsed )) {
				$parsed ['day'] = 1;
			}
			
			if (! array_key_exists ( 'month', $parsed )) {
				$parsed ['month'] = 1;
			}
			
			if (! array_key_exists ( 'year', $parsed )) {
				$parsed ['year'] = 0;
			}
			
			$date = $parsed ['day'] . "." . $parsed ['month'] . "." . $parsed ['year'];
		}
		
		$return = $this->_calcdetail ( $calc, $date, self::DATE_MEDIUM, 'de' );
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Sets a new date for the date object. Format defines how to parse the date string.
	 * Also a complete date with time can be given, but only the date is used for setting.
	 * For example: MMMM.yy HH:mm-> May.07 22:11 => 01.May.07 00:00
	 * Returned is the new date object and the existing time is left as it was before
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date to set
	 * @param  string                          $format  OPTIONAL Date format for parsing
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setDate($date, $format = null, $locale = null) {
		return $this->_date ( 'set', $date, $format, $locale );
	}
	
	/**
	 * Adds a date to the existing date object. Format defines how to parse the date string.
	 * If only parts are given the other parts are set to 0.
	 * If no format is given, the standardformat of this locale is used.
	 * For example: MM.dd.YYYY -> 10 -> +10 months
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date to add
	 * @param  string                          $format  OPTIONAL Date format for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addDate($date, $format = null, $locale = null) {
		return $this->_date ( 'add', $date, $format, $locale );
	}
	
	/**
	 * Subtracts a date from the existing date object. Format defines how to parse the date string.
	 * If only parts are given the other parts are set to 0.
	 * If no format is given, the standardformat of this locale is used.
	 * For example: MM.dd.YYYY -> 10 -> -10 months
	 * Be aware: Subtracting 2 months is not equal to Adding -2 months !!!
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date to sub
	 * @param  string                          $format  OPTIONAL Date format for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subDate($date, $format = null, $locale = null) {
		return $this->_date ( 'sub', $date, $format, $locale );
	}
	
	/**
	 * Compares the date from the existing date object, ignoring the time.
	 * Format defines how to parse the date string.
	 * If only parts are given the other parts are set to 0.
	 * If no format is given, the standardformat of this locale is used.
	 * For example: 10.01.2000 => 10.02.1999 -> false
	 *
	 * @param  string|integer|array|Zend_Date  $date    Date to compare
	 * @param  string                          $format  OPTIONAL Date format for parsing input
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareDate($date, $format = null, $locale = null) {
		return $this->_date ( 'cmp', $date, $format, $locale );
	}
	
	/**
	 * Returns the full ISO 8601 date from the date object.
	 * Always the complete ISO 8601 specifiction is used. If an other ISO date is needed
	 * (ISO 8601 defines several formats) use toString() instead.
	 * This function does not return the ISO date as object. Use copy() instead.
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return string
	 */
	public function getIso($locale = null) {
		return $this->toString ( self::ISO_8601, 'iso', $locale );
	}
	
	/**
	 * Sets a new date for the date object. Not given parts are set to default.
	 * Only supported ISO 8601 formats are accepted.
	 * For example: 050901 -> 01.Sept.2005 00:00:00, 20050201T10:00:30 -> 01.Feb.2005 10h00m30s
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    ISO Date to set
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setIso($date, $locale = null) {
		return $this->_calcvalue ( 'set', $date, 'iso', self::ISO_8601, $locale );
	}
	
	/**
	 * Adds a ISO date to the date object. Not given parts are set to default.
	 * Only supported ISO 8601 formats are accepted.
	 * For example: 050901 -> + 01.Sept.2005 00:00:00, 10:00:00 -> +10h
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    ISO Date to add
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addIso($date, $locale = null) {
		return $this->_calcvalue ( 'add', $date, 'iso', self::ISO_8601, $locale );
	}
	
	/**
	 * Subtracts a ISO date from the date object. Not given parts are set to default.
	 * Only supported ISO 8601 formats are accepted.
	 * For example: 050901 -> - 01.Sept.2005 00:00:00, 10:00:00 -> -10h
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    ISO Date to sub
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subIso($date, $locale = null) {
		return $this->_calcvalue ( 'sub', $date, 'iso', self::ISO_8601, $locale );
	}
	
	/**
	 * Compares a ISO date with the date object. Not given parts are set to default.
	 * Only supported ISO 8601 formats are accepted.
	 * For example: 050901 -> - 01.Sept.2005 00:00:00, 10:00:00 -> -10h
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|Zend_Date  $date    ISO Date to sub
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareIso($date, $locale = null) {
		return $this->_calcvalue ( 'cmp', $date, 'iso', self::ISO_8601, $locale );
	}
	
	/**
	 * Returns a RFC 822 compilant datestring from the date object.
	 * This function does not return the RFC date as object. Use copy() instead.
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return string
	 */
	public function getArpa($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'D\, d M y H\:i\:s O';
		} else {
			$format = self::RFC_822;
		}
		
		return $this->toString ( $format, 'iso', $locale );
	}
	
	/**
	 * Sets a RFC 822 date as new date for the date object.
	 * Only RFC 822 compilant date strings are accepted.
	 * For example: Sat, 14 Feb 09 00:31:30 +0100
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    RFC 822 to set
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setArpa($date, $locale = null) {
		return $this->_calcvalue ( 'set', $date, 'arpa', self::RFC_822, $locale );
	}
	
	/**
	 * Adds a RFC 822 date to the date object.
	 * ARPA messages are used in emails or HTTP Headers.
	 * Only RFC 822 compilant date strings are accepted.
	 * For example: Sat, 14 Feb 09 00:31:30 +0100
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    RFC 822 Date to add
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addArpa($date, $locale = null) {
		return $this->_calcvalue ( 'add', $date, 'arpa', self::RFC_822, $locale );
	}
	
	/**
	 * Subtracts a RFC 822 date from the date object.
	 * ARPA messages are used in emails or HTTP Headers.
	 * Only RFC 822 compilant date strings are accepted.
	 * For example: Sat, 14 Feb 09 00:31:30 +0100
	 * Returned is the new date object
	 *
	 * @param  string|integer|Zend_Date  $date    RFC 822 Date to sub
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subArpa($date, $locale = null) {
		return $this->_calcvalue ( 'sub', $date, 'arpa', self::RFC_822, $locale );
	}
	
	/**
	 * Compares a RFC 822 compilant date with the date object.
	 * ARPA messages are used in emails or HTTP Headers.
	 * Only RFC 822 compilant date strings are accepted.
	 * For example: Sat, 14 Feb 09 00:31:30 +0100
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|Zend_Date  $date    RFC 822 Date to sub
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareArpa($date, $locale = null) {
		return $this->_calcvalue ( 'cmp', $date, 'arpa', self::RFC_822, $locale );
	}
	
	/**
	 * Check if location is supported
	 *
	 * @param array $location locations array
	 * @return $horizon float
	 */
	private function _checkLocation($location) {
		if (! isset ( $location ['longitude'] ) or ! isset ( $location ['latitude'] )) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'Location must include \'longitude\' and \'latitude\'', 0, null, $location );
		}
		if (($location ['longitude'] > 180) or ($location ['longitude'] < - 180)) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'Longitude must be between -180 and 180', 0, null, $location );
		}
		if (($location ['latitude'] > 90) or ($location ['latitude'] < - 90)) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'Latitude must be between -90 and 90', 0, null, $location );
		}
		
		if (! isset ( $location ['horizon'] )) {
			$location ['horizon'] = 'effective';
		}
		
		switch ($location ['horizon']) {
			case 'civil' :
				return - 0.104528;
				break;
			case 'nautic' :
				return - 0.207912;
				break;
			case 'astronomic' :
				return - 0.309017;
				break;
			default :
				return - 0.0145439;
				break;
		}
	}
	
	/**
	 * Returns the time of sunrise for this date and a given location as new date object
	 * For a list of cities and correct locations use the class Zend_Date_Cities
	 *
	 * @param array $location location of sunrise
	 * ['horizon']   -> civil, nautic, astronomical, effective (default)
	 * ['longitude'] -> longitude of location
	 * ['latitude']  -> latitude of location
	 * @return Zend_Date
	 * @throws Zend_Date_Exception
	 */
	public function getSunrise($location) {
		$horizon = $this->_checkLocation ( $location );
		$result = clone $this;
		$result->set ( $this->calcSun ( $location, $horizon, true ), self::TIMESTAMP );
		return $result;
	}
	
	/**
	 * Returns the time of sunset for this date and a given location as new date object
	 * For a list of cities and correct locations use the class Zend_Date_Cities
	 *
	 * @param array $location location of sunset
	 * ['horizon']   -> civil, nautic, astronomical, effective (default)
	 * ['longitude'] -> longitude of location
	 * ['latitude']  -> latitude of location
	 * @return Zend_Date
	 * @throws Zend_Date_Exception
	 */
	public function getSunset($location) {
		$horizon = $this->_checkLocation ( $location );
		$result = clone $this;
		$result->set ( $this->calcSun ( $location, $horizon, false ), self::TIMESTAMP );
		return $result;
	}
	
	/**
	 * Returns an array with the sunset and sunrise dates for all horizon types
	 * For a list of cities and correct locations use the class Zend_Date_Cities
	 *
	 * @param array $location location of suninfo
	 * ['horizon']   -> civil, nautic, astronomical, effective (default)
	 * ['longitude'] -> longitude of location
	 * ['latitude']  -> latitude of location
	 * @return array - [sunset|sunrise][effective|civil|nautic|astronomic]
	 * @throws Zend_Date_Exception
	 */
	public function getSunInfo($location) {
		$suninfo = array ();
		for($i = 0; $i < 4; ++ $i) {
			switch ($i) {
				case 0 :
					$location ['horizon'] = 'effective';
					break;
				case 1 :
					$location ['horizon'] = 'civil';
					break;
				case 2 :
					$location ['horizon'] = 'nautic';
					break;
				case 3 :
					$location ['horizon'] = 'astronomic';
					break;
			}
			$horizon = $this->_checkLocation ( $location );
			$result = clone $this;
			$result->set ( $this->calcSun ( $location, $horizon, true ), self::TIMESTAMP );
			$suninfo ['sunrise'] [$location ['horizon']] = $result;
			$result = clone $this;
			$result->set ( $this->calcSun ( $location, $horizon, false ), self::TIMESTAMP );
			$suninfo ['sunset'] [$location ['horizon']] = $result;
		}
		return $suninfo;
	}
	
	/**
	 * Check a given year for leap year.
	 *
	 * @param  integer|array|Zend_Date  $year  Year to check
	 * @return boolean
	 */
	public static function checkLeapYear($year) {
		if ($year instanceof Zend_Date) {
			$year = ( int ) $year->toString ( self::YEAR, 'iso' );
		}
		
		if (is_array ( $year )) {
			if (isset ( $year ['year'] ) === true) {
				$year = $year ['year'];
			} else {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "no year given in array" );
			}
		}
		
		if (! is_numeric ( $year )) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "year ($year) has to be integer for checkLeapYear()", 0, null, $year );
		}
		
		return ( bool ) parent::isYearLeapYear ( $year );
	}
	
	/**
	 * Returns true, if the year is a leap year.
	 *
	 * @return boolean
	 */
	public function isLeapYear() {
		return self::checkLeapYear ( $this );
	}
	
	/**
	 * Returns if the set date is todays date
	 *
	 * @return boolean
	 */
	public function isToday() {
		$today = $this->date ( 'Ymd', $this->_getTime () );
		$day = $this->date ( 'Ymd', $this->getUnixTimestamp () );
		return ($today == $day);
	}
	
	/**
	 * Returns if the set date is yesterdays date
	 *
	 * @return boolean
	 */
	public function isYesterday() {
		list ( $year, $month, $day ) = explode ( '-', $this->date ( 'Y-m-d', $this->_getTime () ) );
		// adjusts for leap days and DST changes that are timezone specific
		$yesterday = $this->date ( 'Ymd', $this->mktime ( 0, 0, 0, $month, $day - 1, $year ) );
		$day = $this->date ( 'Ymd', $this->getUnixTimestamp () );
		return $day == $yesterday;
	}
	
	/**
	 * Returns if the set date is tomorrows date
	 *
	 * @return boolean
	 */
	public function isTomorrow() {
		list ( $year, $month, $day ) = explode ( '-', $this->date ( 'Y-m-d', $this->_getTime () ) );
		// adjusts for leap days and DST changes that are timezone specific
		$tomorrow = $this->date ( 'Ymd', $this->mktime ( 0, 0, 0, $month, $day + 1, $year ) );
		$day = $this->date ( 'Ymd', $this->getUnixTimestamp () );
		return $day == $tomorrow;
	}
	
	/**
	 * Returns the actual date as new date object
	 *
	 * @param  string|Zend_Locale        $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public static function now($locale = null) {
		return new Zend_Date ( time (), self::TIMESTAMP, $locale );
	}
	
	/**
	 * Calculate date details
	 *
	 * @param  string                          $calc    Calculation to make
	 * @param  string|integer|array|Zend_Date  $date    Date or Part to calculate
	 * @param  string                          $part    Datepart for Calculation
	 * @param  string|Zend_Locale              $locale  Locale for parsing input
	 * @return integer|string  new date
	 * @throws Zend_Date_Exception
	 */
	private function _calcdetail($calc, $date, $type, $locale) {
		$old = false;
		if (self::$_options ['format_type'] == 'php') {
			self::$_options ['format_type'] = 'iso';
			$old = true;
		}
		
		switch ($calc) {
			case 'set' :
				$return = $this->set ( $date, $type, $locale );
				break;
			case 'add' :
				$return = $this->add ( $date, $type, $locale );
				break;
			case 'sub' :
				$return = $this->sub ( $date, $type, $locale );
				break;
			default :
				$return = $this->compare ( $date, $type, $locale );
				break;
		}
		
		if ($old) {
			self::$_options ['format_type'] = 'php';
		}
		
		return $return;
	}
	
	/**
	 * Internal calculation, returns the requested date type
	 *
	 * @param  string                    $calc    Calculation to make
	 * @param  string|integer|Zend_Date  $value   Datevalue to calculate with, if null the actual value is taken
	 * @param  string|Zend_Locale        $locale  Locale for parsing input
	 * @return integer|Zend_Date  new date
	 * @throws Zend_Date_Exception
	 */
	private function _calcvalue($calc, $value, $type, $parameter, $locale) {
		if ($value === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "parameter $type must be set, null is not allowed" );
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if ($value instanceof Zend_Date) {
			// extract value from object
			$value = $value->toString ( $parameter, 'iso', $locale );
		} else if (! is_array ( $value ) && ! is_numeric ( $value ) && ($type != 'iso') && ($type != 'arpa')) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "invalid $type ($value) operand", 0, null, $value );
		}
		
		$return = $this->_calcdetail ( $calc, $value, $parameter, $locale );
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Returns only the year from the date object as new object.
	 * For example: 10.May.2000 10:30:00 -> 01.Jan.2000 00:00:00
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getYear($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'Y';
		} else {
			$format = self::YEAR;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Sets a new year
	 * If the year is between 0 and 69, 2000 will be set (2000-2069)
	 * If the year if between 70 and 99, 1999 will be set (1970-1999)
	 * 3 or 4 digit years are set as expected. If you need to set year 0-99
	 * use set() instead.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $date    Year to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setYear($year, $locale = null) {
		return $this->_calcvalue ( 'set', $year, 'year', self::YEAR, $locale );
	}
	
	/**
	 * Adds the year to the existing date object
	 * If the year is between 0 and 69, 2000 will be added (2000-2069)
	 * If the year if between 70 and 99, 1999 will be added (1970-1999)
	 * 3 or 4 digit years are added as expected. If you need to add years from 0-99
	 * use add() instead.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $date    Year to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addYear($year, $locale = null) {
		return $this->_calcvalue ( 'add', $year, 'year', self::YEAR, $locale );
	}
	
	/**
	 * Subs the year from the existing date object
	 * If the year is between 0 and 69, 2000 will be subtracted (2000-2069)
	 * If the year if between 70 and 99, 1999 will be subtracted (1970-1999)
	 * 3 or 4 digit years are subtracted as expected. If you need to subtract years from 0-99
	 * use sub() instead.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $date    Year to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subYear($year, $locale = null) {
		return $this->_calcvalue ( 'sub', $year, 'year', self::YEAR, $locale );
	}
	
	/**
	 * Compares the year with the existing date object, ignoring other date parts.
	 * For example: 10.03.2000 -> 15.02.2000 -> true
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $year    Year to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareYear($year, $locale = null) {
		return $this->_calcvalue ( 'cmp', $year, 'year', self::YEAR, $locale );
	}
	
	/**
	 * Returns only the month from the date object as new object.
	 * For example: 10.May.2000 10:30:00 -> 01.May.1970 00:00:00
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getMonth($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'm';
		} else {
			$format = self::MONTH;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Returns the calculated month
	 *
	 * @param  string                          $calc    Calculation to make
	 * @param  string|integer|array|Zend_Date  $month   Month to calculate with, if null the actual month is taken
	 * @param  string|Zend_Locale              $locale  Locale for parsing input
	 * @return integer|Zend_Date  new time
	 * @throws Zend_Date_Exception
	 */
	private function _month($calc, $month, $locale) {
		if ($month === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $month must be set, null is not allowed' );
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if ($month instanceof Zend_Date) {
			// extract month from object
			$found = $month->toString ( self::MONTH_SHORT, 'iso', $locale );
		} else {
			if (is_numeric ( $month )) {
				$found = $month;
			} else if (is_array ( $month )) {
				if (isset ( $month ['month'] ) === true) {
					$month = $month ['month'];
				} else {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "no month given in array" );
				}
			} else {
				$monthlist = Zend_Locale_Data::getList ( $locale, 'month' );
				$monthlist2 = Zend_Locale_Data::getList ( $locale, 'month', array ('gregorian', 'format', 'abbreviated' ) );
				
				$monthlist = array_merge ( $monthlist, $monthlist2 );
				$found = 0;
				$cnt = 0;
				foreach ( $monthlist as $key => $value ) {
					if (strtoupper ( $value ) == strtoupper ( $month )) {
						$found = ($key % 12) + 1;
						break;
					}
					++ $cnt;
				}
				if ($found == 0) {
					foreach ( $monthlist2 as $key => $value ) {
						if (strtoupper ( iconv_substr ( $value, 0, 1, 'UTF-8' ) ) == strtoupper ( $month )) {
							$found = $key + 1;
							break;
						}
						++ $cnt;
					}
				}
				if ($found == 0) {
					require_once 'Zend/Date/Exception.php';
					throw new Zend_Date_Exception ( "unknown month name ($month)", 0, null, $month );
				}
			}
		}
		$return = $this->_calcdetail ( $calc, $found, self::MONTH_SHORT, $locale );
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Sets a new month
	 * The month can be a number or a string. Setting months lower then 0 and greater then 12
	 * will result in adding or subtracting the relevant year. (12 months equal one year)
	 * If a localized monthname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $month   Month to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setMonth($month, $locale = null) {
		return $this->_month ( 'set', $month, $locale );
	}
	
	/**
	 * Adds months to the existing date object.
	 * The month can be a number or a string. Adding months lower then 0 and greater then 12
	 * will result in adding or subtracting the relevant year. (12 months equal one year)
	 * If a localized monthname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $month   Month to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addMonth($month, $locale = null) {
		return $this->_month ( 'add', $month, $locale );
	}
	
	/**
	 * Subtracts months from the existing date object.
	 * The month can be a number or a string. Subtracting months lower then 0 and greater then 12
	 * will result in adding or subtracting the relevant year. (12 months equal one year)
	 * If a localized monthname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 *
	 * @param  string|integer|array|Zend_Date  $month   Month to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subMonth($month, $locale = null) {
		return $this->_month ( 'sub', $month, $locale );
	}
	
	/**
	 * Compares the month with the existing date object, ignoring other date parts.
	 * For example: 10.03.2000 -> 15.03.1950 -> true
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $month   Month to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareMonth($month, $locale = null) {
		return $this->_month ( 'cmp', $month, $locale );
	}
	
	/**
	 * Returns the day as new date object
	 * Example: 20.May.1986 -> 20.Jan.1970 00:00:00
	 *
	 * @param Zend_Locale $locale OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getDay($locale = null) {
		return $this->copyPart ( self::DAY_SHORT, $locale );
	}
	
	/**
	 * Returns the calculated day
	 *
	 * @param string      $calc    Type of calculation to make
	 * @param Zend_Date   $day     Day to calculate, when null the actual day is calculated
	 * @param Zend_Locale $locale  Locale for parsing input
	 * @return Zend_Date|integer
	 */
	private function _day($calc, $day, $locale) {
		if ($day === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $day must be set, null is not allowed' );
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if ($day instanceof Zend_Date) {
			$day = $day->toString ( self::DAY_SHORT, 'iso', $locale );
		}
		
		if (is_numeric ( $day )) {
			$type = self::DAY_SHORT;
		} else if (is_array ( $day )) {
			if (isset ( $day ['day'] ) === true) {
				$day = $day ['day'];
				$type = self::WEEKDAY;
			} else {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "no day given in array" );
			}
		} else {
			switch (iconv_strlen ( $day, 'UTF-8' )) {
				case 1 :
					$type = self::WEEKDAY_NARROW;
					break;
				case 2 :
					$type = self::WEEKDAY_NAME;
					break;
				case 3 :
					$type = self::WEEKDAY_SHORT;
					break;
				default :
					$type = self::WEEKDAY;
					break;
			}
		}
		$return = $this->_calcdetail ( $calc, $day, $type, $locale );
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Sets a new day
	 * The day can be a number or a string. Setting days lower then 0 or greater than the number of this months days
	 * will result in adding or subtracting the relevant month.
	 * If a localized dayname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 * Example: setDay('Montag', 'de_AT'); will set the monday of this week as day.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Day to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setDay($day, $locale = null) {
		return $this->_day ( 'set', $day, $locale );
	}
	
	/**
	 * Adds days to the existing date object.
	 * The day can be a number or a string. Adding days lower then 0 or greater than the number of this months days
	 * will result in adding or subtracting the relevant month.
	 * If a localized dayname is given it will be parsed with the default locale or the optional
	 * set locale.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Day to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addDay($day, $locale = null) {
		return $this->_day ( 'add', $day, $locale );
	}
	
	/**
	 * Subtracts days from the existing date object.
	 * The day can be a number or a string. Subtracting days lower then 0 or greater than the number of this months days
	 * will result in adding or subtracting the relevant month.
	 * If a localized dayname is given it will be parsed with the default locale or the optional
	 * set locale.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Day to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subDay($day, $locale = null) {
		return $this->_day ( 'sub', $day, $locale );
	}
	
	/**
	 * Compares the day with the existing date object, ignoring other date parts.
	 * For example: 'Monday', 'en' -> 08.Jan.2007 -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $day     Day to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareDay($day, $locale = null) {
		return $this->_day ( 'cmp', $day, $locale );
	}
	
	/**
	 * Returns the weekday as new date object
	 * Weekday is always from 1-7
	 * Example: 09-Jan-2007 -> 2 = Tuesday -> 02-Jan-1970 (when 02.01.1970 is also Tuesday)
	 *
	 * @param Zend_Locale $locale OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getWeekday($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'l';
		} else {
			$format = self::WEEKDAY;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Returns the calculated weekday
	 *
	 * @param  string      $calc     Type of calculation to make
	 * @param  Zend_Date   $weekday  Weekday to calculate, when null the actual weekday is calculated
	 * @param  Zend_Locale $locale   Locale for parsing input
	 * @return Zend_Date|integer
	 * @throws Zend_Date_Exception
	 */
	private function _weekday($calc, $weekday, $locale) {
		if ($weekday === null) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'parameter $weekday must be set, null is not allowed' );
		}
		
		if ($locale === null) {
			$locale = $this->getLocale ();
		}
		
		if ($weekday instanceof Zend_Date) {
			$weekday = $weekday->toString ( self::WEEKDAY_8601, 'iso', $locale );
		}
		
		if (is_numeric ( $weekday )) {
			$type = self::WEEKDAY_8601;
		} else if (is_array ( $weekday )) {
			if (isset ( $weekday ['weekday'] ) === true) {
				$weekday = $weekday ['weekday'];
				$type = self::WEEKDAY;
			} else {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception ( "no weekday given in array" );
			}
		} else {
			switch (iconv_strlen ( $weekday, 'UTF-8' )) {
				case 1 :
					$type = self::WEEKDAY_NARROW;
					break;
				case 2 :
					$type = self::WEEKDAY_NAME;
					break;
				case 3 :
					$type = self::WEEKDAY_SHORT;
					break;
				default :
					$type = self::WEEKDAY;
					break;
			}
		}
		$return = $this->_calcdetail ( $calc, $weekday, $type, $locale );
		if ($calc != 'cmp') {
			return $this;
		}
		return $return;
	}
	
	/**
	 * Sets a new weekday
	 * The weekday can be a number or a string. If a localized weekday name is given,
	 * then it will be parsed as a date in $locale (defaults to the same locale as $this).
	 * Returned is the new date object.
	 * Example: setWeekday(3); will set the wednesday of this week as day.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Weekday to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setWeekday($weekday, $locale = null) {
		return $this->_weekday ( 'set', $weekday, $locale );
	}
	
	/**
	 * Adds weekdays to the existing date object.
	 * The weekday can be a number or a string.
	 * If a localized dayname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 * Example: addWeekday(3); will add the difference of days from the begining of the month until
	 * wednesday.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Weekday to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addWeekday($weekday, $locale = null) {
		return $this->_weekday ( 'add', $weekday, $locale );
	}
	
	/**
	 * Subtracts weekdays from the existing date object.
	 * The weekday can be a number or a string.
	 * If a localized dayname is given it will be parsed with the default locale or the optional
	 * set locale.
	 * Returned is the new date object
	 * Example: subWeekday(3); will subtract the difference of days from the begining of the month until
	 * wednesday.
	 *
	 * @param  string|integer|array|Zend_Date  $month   Weekday to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subWeekday($weekday, $locale = null) {
		return $this->_weekday ( 'sub', $weekday, $locale );
	}
	
	/**
	 * Compares the weekday with the existing date object, ignoring other date parts.
	 * For example: 'Monday', 'en' -> 08.Jan.2007 -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $weekday  Weekday to compare
	 * @param  string|Zend_Locale              $locale   OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareWeekday($weekday, $locale = null) {
		return $this->_weekday ( 'cmp', $weekday, $locale );
	}
	
	/**
	 * Returns the day of year as new date object
	 * Example: 02.Feb.1986 10:00:00 -> 02.Feb.1970 00:00:00
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getDayOfYear($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'D';
		} else {
			$format = self::DAY_OF_YEAR;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Sets a new day of year
	 * The day of year is always a number.
	 * Returned is the new date object
	 * Example: 04.May.2004 -> setDayOfYear(10) -> 10.Jan.2004
	 *
	 * @param  string|integer|array|Zend_Date  $day     Day of Year to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setDayOfYear($day, $locale = null) {
		return $this->_calcvalue ( 'set', $day, 'day of year', self::DAY_OF_YEAR, $locale );
	}
	
	/**
	 * Adds a day of year to the existing date object.
	 * The day of year is always a number.
	 * Returned is the new date object
	 * Example: addDayOfYear(10); will add 10 days to the existing date object.
	 *
	 * @param  string|integer|array|Zend_Date  $day     Day of Year to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addDayOfYear($day, $locale = null) {
		return $this->_calcvalue ( 'add', $day, 'day of year', self::DAY_OF_YEAR, $locale );
	}
	
	/**
	 * Subtracts a day of year from the existing date object.
	 * The day of year is always a number.
	 * Returned is the new date object
	 * Example: subDayOfYear(10); will subtract 10 days from the existing date object.
	 *
	 * @param  string|integer|array|Zend_Date  $day     Day of Year to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subDayOfYear($day, $locale = null) {
		return $this->_calcvalue ( 'sub', $day, 'day of year', self::DAY_OF_YEAR, $locale );
	}
	
	/**
	 * Compares the day of year with the existing date object.
	 * For example: compareDayOfYear(33) -> 02.Feb.2007 -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $day     Day of Year to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareDayOfYear($day, $locale = null) {
		return $this->_calcvalue ( 'cmp', $day, 'day of year', self::DAY_OF_YEAR, $locale );
	}
	
	/**
	 * Returns the hour as new date object
	 * Example: 02.Feb.1986 10:30:25 -> 01.Jan.1970 10:00:00
	 *
	 * @param Zend_Locale $locale OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getHour($locale = null) {
		return $this->copyPart ( self::HOUR, $locale );
	}
	
	/**
	 * Sets a new hour
	 * The hour is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> setHour(7); -> 04.May.1993 07:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $hour    Hour to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setHour($hour, $locale = null) {
		return $this->_calcvalue ( 'set', $hour, 'hour', self::HOUR_SHORT, $locale );
	}
	
	/**
	 * Adds hours to the existing date object.
	 * The hour is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> addHour(12); -> 05.May.1993 01:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $hour    Hour to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addHour($hour, $locale = null) {
		return $this->_calcvalue ( 'add', $hour, 'hour', self::HOUR_SHORT, $locale );
	}
	
	/**
	 * Subtracts hours from the existing date object.
	 * The hour is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> subHour(6); -> 05.May.1993 07:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $hour    Hour to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subHour($hour, $locale = null) {
		return $this->_calcvalue ( 'sub', $hour, 'hour', self::HOUR_SHORT, $locale );
	}
	
	/**
	 * Compares the hour with the existing date object.
	 * For example: 10:30:25 -> compareHour(10) -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $hour    Hour to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareHour($hour, $locale = null) {
		return $this->_calcvalue ( 'cmp', $hour, 'hour', self::HOUR_SHORT, $locale );
	}
	
	/**
	 * Returns the minute as new date object
	 * Example: 02.Feb.1986 10:30:25 -> 01.Jan.1970 00:30:00
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getMinute($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'i';
		} else {
			$format = self::MINUTE;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Sets a new minute
	 * The minute is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> setMinute(29); -> 04.May.1993 13:29:25
	 *
	 * @param  string|integer|array|Zend_Date  $minute  Minute to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setMinute($minute, $locale = null) {
		return $this->_calcvalue ( 'set', $minute, 'minute', self::MINUTE_SHORT, $locale );
	}
	
	/**
	 * Adds minutes to the existing date object.
	 * The minute is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> addMinute(65); -> 04.May.1993 13:12:25
	 *
	 * @param  string|integer|array|Zend_Date  $minute  Minute to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addMinute($minute, $locale = null) {
		return $this->_calcvalue ( 'add', $minute, 'minute', self::MINUTE_SHORT, $locale );
	}
	
	/**
	 * Subtracts minutes from the existing date object.
	 * The minute is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> subMinute(9); -> 04.May.1993 12:58:25
	 *
	 * @param  string|integer|array|Zend_Date  $minute  Minute to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subMinute($minute, $locale = null) {
		return $this->_calcvalue ( 'sub', $minute, 'minute', self::MINUTE_SHORT, $locale );
	}
	
	/**
	 * Compares the minute with the existing date object.
	 * For example: 10:30:25 -> compareMinute(30) -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date  $minute  Hour to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareMinute($minute, $locale = null) {
		return $this->_calcvalue ( 'cmp', $minute, 'minute', self::MINUTE_SHORT, $locale );
	}
	
	/**
	 * Returns the second as new date object
	 * Example: 02.Feb.1986 10:30:25 -> 01.Jan.1970 00:00:25
	 *
	 * @param  string|Zend_Locale  $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getSecond($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 's';
		} else {
			$format = self::SECOND;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Sets new seconds to the existing date object.
	 * The second is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> setSecond(100); -> 04.May.1993 13:08:40
	 *
	 * @param  string|integer|array|Zend_Date $second Second to set
	 * @param  string|Zend_Locale             $locale (Optional) Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setSecond($second, $locale = null) {
		return $this->_calcvalue ( 'set', $second, 'second', self::SECOND_SHORT, $locale );
	}
	
	/**
	 * Adds seconds to the existing date object.
	 * The second is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> addSecond(65); -> 04.May.1993 13:08:30
	 *
	 * @param  string|integer|array|Zend_Date $second Second to add
	 * @param  string|Zend_Locale             $locale (Optional) Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addSecond($second, $locale = null) {
		return $this->_calcvalue ( 'add', $second, 'second', self::SECOND_SHORT, $locale );
	}
	
	/**
	 * Subtracts seconds from the existing date object.
	 * The second is always a number.
	 * Returned is the new date object
	 * Example: 04.May.1993 13:07:25 -> subSecond(10); -> 04.May.1993 13:07:15
	 *
	 * @param  string|integer|array|Zend_Date $second Second to sub
	 * @param  string|Zend_Locale             $locale (Optional) Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subSecond($second, $locale = null) {
		return $this->_calcvalue ( 'sub', $second, 'second', self::SECOND_SHORT, $locale );
	}
	
	/**
	 * Compares the second with the existing date object.
	 * For example: 10:30:25 -> compareSecond(25) -> 0
	 * Returns if equal, earlier or later
	 *
	 * @param  string|integer|array|Zend_Date $second Second to compare
	 * @param  string|Zend_Locale             $locale (Optional) Locale for parsing input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 * @throws Zend_Date_Exception
	 */
	public function compareSecond($second, $locale = null) {
		return $this->_calcvalue ( 'cmp', $second, 'second', self::SECOND_SHORT, $locale );
	}
	
	/**
	 * Returns the precision for fractional seconds
	 *
	 * @return integer
	 */
	public function getFractionalPrecision() {
		return $this->_precision;
	}
	
	/**
	 * Sets a new precision for fractional seconds
	 *
	 * @param  integer $precision Precision for the fractional datepart 3 = milliseconds
	 * @throws Zend_Date_Exception
	 * @return Zend_Date Provides fluid interface
	 */
	public function setFractionalPrecision($precision) {
		if (! intval ( $precision ) or ($precision < 0) or ($precision > 9)) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "precision ($precision) must be a positive integer less than 10", 0, null, $precision );
		}
		
		$this->_precision = ( int ) $precision;
		if ($this->_precision < strlen ( $this->_fractional )) {
			$this->_fractional = substr ( $this->_fractional, 0, $this->_precision );
		} else {
			$this->_fractional = str_pad ( $this->_fractional, $this->_precision, '0', STR_PAD_RIGHT );
		}
		
		return $this;
	}
	
	/**
	 * Returns the milliseconds of the date object
	 *
	 * @return string
	 */
	public function getMilliSecond() {
		return $this->_fractional;
	}
	
	/**
	 * Sets new milliseconds for the date object
	 * Example: setMilliSecond(550, 2) -> equals +5 Sec +50 MilliSec
	 *
	 * @param  integer|Zend_Date $milli     (Optional) Millisecond to set, when null the actual millisecond is set
	 * @param  integer           $precision (Optional) Fraction precision of the given milliseconds
	 * @return Zend_Date Provides fluid interface
	 */
	public function setMilliSecond($milli = null, $precision = null) {
		if ($milli === null) {
			list ( $milli, $time ) = explode ( " ", microtime () );
			$milli = intval ( $milli );
			$precision = 6;
		} else if (! is_numeric ( $milli )) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "invalid milli second ($milli) operand", 0, null, $milli );
		}
		
		if ($precision === null) {
			$precision = $this->_precision;
		}
		
		if (! is_int ( $precision ) || $precision < 1 || $precision > 9) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "precision ($precision) must be a positive integer less than 10", 0, null, $precision );
		}
		
		$this->_fractional = 0;
		$this->addMilliSecond ( $milli, $precision );
		return $this;
	}
	
	/**
	 * Adds milliseconds to the date object
	 *
	 * @param  integer|Zend_Date $milli     (Optional) Millisecond to add, when null the actual millisecond is added
	 * @param  integer           $precision (Optional) Fractional precision for the given milliseconds
	 * @return Zend_Date Provides fluid interface
	 */
	public function addMilliSecond($milli = null, $precision = null) {
		if ($milli === null) {
			list ( $milli, $time ) = explode ( " ", microtime () );
			$milli = intval ( $milli );
		} else if (! is_numeric ( $milli )) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "invalid milli second ($milli) operand", 0, null, $milli );
		}
		
		if ($precision === null) {
			$precision = strlen ( $milli );
			if ($milli < 0) {
				-- $precision;
			}
		}
		
		if (! is_int ( $precision ) || $precision < 1 || $precision > 9) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "precision ($precision) must be a positive integer less than 10", 0, null, $precision );
		}
		
		$this->_fractional += $milli;
		
		// Add/sub milliseconds + add/sub seconds
		$max = pow ( 10, $this->_precision );
		// Milli includes seconds
		if ($this->_fractional >= $max) {
			while ( $this->_fractional >= $max ) {
				$this->addSecond ( 1 );
				$this->_fractional -= $max;
			}
		}
		
		if ($this->_fractional < 0) {
			while ( $this->_fractional < 0 ) {
				$this->subSecond ( 1 );
				$this->_fractional += $max;
			}
		}
		
		if ($this->_precision > strlen ( $this->_fractional )) {
			$this->_fractional = str_pad ( $this->_fractional, $this->_precision, '0', STR_PAD_LEFT );
		}
		
		return $this;
	}
	
	/**
	 * Subtracts a millisecond
	 *
	 * @param  integer|Zend_Date $milli     (Optional) Millisecond to sub, when null the actual millisecond is subtracted
	 * @param  integer           $precision (Optional) Fractional precision for the given milliseconds
	 * @return Zend_Date Provides fluid interface
	 */
	public function subMilliSecond($milli = null, $precision = null) {
		$this->addMilliSecond ( 0 - $milli, $precision );
		return $this;
	}
	
	/**
	 * Compares only the millisecond part, returning the difference
	 *
	 * @param  integer|Zend_Date  $milli  OPTIONAL Millisecond to compare, when null the actual millisecond is compared
	 * @param  integer            $precision  OPTIONAL Fractional precision for the given milliseconds
	 * @throws Zend_Date_Exception On invalid input
	 * @return integer  0 = equal, 1 = later, -1 = earlier
	 */
	public function compareMilliSecond($milli = null, $precision = null) {
		if ($milli === null) {
			list ( $milli, $time ) = explode ( " ", microtime () );
			$milli = intval ( $milli );
		} else if (is_numeric ( $milli ) === false) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "invalid milli second ($milli) operand", 0, null, $milli );
		}
		
		if ($precision === null) {
			$precision = strlen ( $milli );
		} else if (! is_int ( $precision ) || $precision < 1 || $precision > 9) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( "precision ($precision) must be a positive integer less than 10", 0, null, $precision );
		}
		
		if ($precision === 0) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( 'precision is 0' );
		}
		
		if ($precision != $this->_precision) {
			if ($precision > $this->_precision) {
				$diff = $precision - $this->_precision;
				$milli = ( int ) ($milli / (10 * $diff));
			} else {
				$diff = $this->_precision - $precision;
				$milli = ( int ) ($milli * (10 * $diff));
			}
		}
		
		$comp = $this->_fractional - $milli;
		if ($comp < 0) {
			return - 1;
		} else if ($comp > 0) {
			return 1;
		}
		return 0;
	}
	
	/**
	 * Returns the week as new date object using monday as begining of the week
	 * Example: 12.Jan.2007 -> 08.Jan.1970 00:00:00
	 *
	 * @param Zend_Locale $locale OPTIONAL Locale for parsing input
	 * @return Zend_Date
	 */
	public function getWeek($locale = null) {
		if (self::$_options ['format_type'] == 'php') {
			$format = 'W';
		} else {
			$format = self::WEEK;
		}
		
		return $this->copyPart ( $format, $locale );
	}
	
	/**
	 * Sets a new week. The week is always a number. The day of week is not changed.
	 * Returned is the new date object
	 * Example: 09.Jan.2007 13:07:25 -> setWeek(1); -> 02.Jan.2007 13:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $week    Week to set
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function setWeek($week, $locale = null) {
		return $this->_calcvalue ( 'set', $week, 'week', self::WEEK, $locale );
	}
	
	/**
	 * Adds a week. The week is always a number. The day of week is not changed.
	 * Returned is the new date object
	 * Example: 09.Jan.2007 13:07:25 -> addWeek(1); -> 16.Jan.2007 13:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $week    Week to add
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function addWeek($week, $locale = null) {
		return $this->_calcvalue ( 'add', $week, 'week', self::WEEK, $locale );
	}
	
	/**
	 * Subtracts a week. The week is always a number. The day of week is not changed.
	 * Returned is the new date object
	 * Example: 09.Jan.2007 13:07:25 -> subWeek(1); -> 02.Jan.2007 13:07:25
	 *
	 * @param  string|integer|array|Zend_Date  $week    Week to sub
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return Zend_Date Provides fluid interface
	 * @throws Zend_Date_Exception
	 */
	public function subWeek($week, $locale = null) {
		return $this->_calcvalue ( 'sub', $week, 'week', self::WEEK, $locale );
	}
	
	/**
	 * Compares only the week part, returning the difference
	 * Returned is the new date object
	 * Returns if equal, earlier or later
	 * Example: 09.Jan.2007 13:07:25 -> compareWeek(2); -> 0
	 *
	 * @param  string|integer|array|Zend_Date  $week    Week to compare
	 * @param  string|Zend_Locale              $locale  OPTIONAL Locale for parsing input
	 * @return integer 0 = equal, 1 = later, -1 = earlier
	 */
	public function compareWeek($week, $locale = null) {
		return $this->_calcvalue ( 'cmp', $week, 'week', self::WEEK, $locale );
	}
	
	/**
	 * Sets a new standard locale for the date object.
	 * This locale will be used for all functions
	 * Returned is the really set locale.
	 * Example: 'de_XX' will be set to 'de' because 'de_XX' does not exist
	 * 'xx_YY' will be set to 'root' because 'xx' does not exist
	 *
	 * @param  string|Zend_Locale $locale (Optional) Locale for parsing input
	 * @throws Zend_Date_Exception When the given locale does not exist
	 * @return Zend_Date Provides fluent interface
	 */
	public function setLocale($locale = null) {
		try {
			$this->_locale = Zend_Locale::findLocale ( $locale );
		} catch ( Zend_Locale_Exception $e ) {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception ( $e->getMessage (), 0, $e );
		}
		
		return $this;
	}
	
	/**
	 * Returns the actual set locale
	 *
	 * @return string
	 */
	public function getLocale() {
		return $this->_locale;
	}
	
	/**
	 * Checks if the given date is a real date or datepart.
	 * Returns false if a expected datepart is missing or a datepart exceeds its possible border.
	 * But the check will only be done for the expected dateparts which are given by format.
	 * If no format is given the standard dateformat for the actual locale is used.
	 * f.e. 30.February.2007 will return false if format is 'dd.MMMM.YYYY'
	 *
	 * @param  string|array|Zend_Date $date   Date to parse for correctness
	 * @param  string                 $format (Optional) Format for parsing the date string
	 * @param  string|Zend_Locale     $locale (Optional) Locale for parsing date parts
	 * @return boolean                True when all date parts are correct
	 */
	public static function isDate($date, $format = null, $locale = null) {
		if (! is_string ( $date ) && ! is_numeric ( $date ) && ! ($date instanceof Zend_Date) && ! is_array ( $date )) {
			return false;
		}
		
		if (($format !== null) && ($format != 'ee') && ($format != 'ss') && ($format != 'GG') && ($format != 'MM') && ($format != 'EE') && ($format != 'TT') && (Zend_Locale::isLocale ( $format, null, false ))) {
			$locale = $format;
			$format = null;
		}
		
		$locale = Zend_Locale::findLocale ( $locale );
		
		if ($format === null) {
			$format = Zend_Locale_Format::getDateFormat ( $locale );
		} else if ((self::$_options ['format_type'] == 'php') && ! defined ( $format )) {
			$format = Zend_Locale_Format::convertPhpToIsoFormat ( $format );
		}
		
		$format = self::_getLocalizedToken ( $format, $locale );
		if (! is_array ( $date )) {
			try {
				$parsed = Zend_Locale_Format::getDate ( $date, array ('locale' => $locale, 'date_format' => $format, 'format_type' => 'iso', 'fix_date' => false ) );
			} catch ( Zend_Locale_Exception $e ) {
				// Date can not be parsed
				return false;
			}
		} else {
			$parsed = $date;
		}
		
		if (((strpos ( $format, 'Y' ) !== false) or (strpos ( $format, 'y' ) !== false)) and (! isset ( $parsed ['year'] ))) {
			// Year expected but not found
			return false;
		}
		
		if ((strpos ( $format, 'M' ) !== false) and (! isset ( $parsed ['month'] ))) {
			// Month expected but not found
			return false;
		}
		
		if ((strpos ( $format, 'd' ) !== false) and (! isset ( $parsed ['day'] ))) {
			// Day expected but not found
			return false;
		}
		
		if (((strpos ( $format, 'H' ) !== false) or (strpos ( $format, 'h' ) !== false)) and (! isset ( $parsed ['hour'] ))) {
			// Hour expected but not found
			return false;
		}
		
		if ((strpos ( $format, 'm' ) !== false) and (! isset ( $parsed ['minute'] ))) {
			// Minute expected but not found
			return false;
		}
		
		if ((strpos ( $format, 's' ) !== false) and (! isset ( $parsed ['second'] ))) {
			// Second expected  but not found
			return false;
		}
		
		// Set not given dateparts
		if (isset ( $parsed ['hour'] ) === false) {
			$parsed ['hour'] = 12;
		}
		
		if (isset ( $parsed ['minute'] ) === false) {
			$parsed ['minute'] = 0;
		}
		
		if (isset ( $parsed ['second'] ) === false) {
			$parsed ['second'] = 0;
		}
		
		if (isset ( $parsed ['month'] ) === false) {
			$parsed ['month'] = 1;
		}
		
		if (isset ( $parsed ['day'] ) === false) {
			$parsed ['day'] = 1;
		}
		
		if (isset ( $parsed ['year'] ) === false) {
			$parsed ['year'] = 1970;
		}
		
		if (self::isYearLeapYear ( $parsed ['year'] )) {
			$parsed ['year'] = 1972;
		} else {
			$parsed ['year'] = 1971;
		}
		
		$date = new self ( $parsed, null, $locale );
		$timestamp = $date->mktime ( $parsed ['hour'], $parsed ['minute'], $parsed ['second'], $parsed ['month'], $parsed ['day'], $parsed ['year'] );
		
		if ($parsed ['year'] != $date->date ( 'Y', $timestamp )) {
			// Given year differs from parsed year
			return false;
		}
		
		if ($parsed ['month'] != $date->date ( 'n', $timestamp )) {
			// Given month differs from parsed month
			return false;
		}
		
		if ($parsed ['day'] != $date->date ( 'j', $timestamp )) {
			// Given day differs from parsed day
			return false;
		}
		
		if ($parsed ['hour'] != $date->date ( 'G', $timestamp )) {
			// Given hour differs from parsed hour
			return false;
		}
		
		if ($parsed ['minute'] != $date->date ( 'i', $timestamp )) {
			// Given minute differs from parsed minute
			return false;
		}
		
		if ($parsed ['second'] != $date->date ( 's', $timestamp )) {
			// Given second differs from parsed second
			return false;
		}
		
		return true;
	}
	
	/**
	 * Returns the ISO Token for all localized constants
	 *
	 * @param string $token Token to normalize
	 * @param string $locale Locale to search
	 * @return string
	 */
	protected static function _getLocalizedToken($token, $locale) {
		switch ($token) {
			case self::ISO_8601 :
				return "yyyy-MM-ddThh:mm:ss";
				break;
			case self::RFC_2822 :
				return "EEE, dd MMM yyyy HH:mm:ss";
				break;
			case self::DATES :
				return Zend_Locale_Data::getContent ( $locale, 'date' );
				break;
			case self::DATE_FULL :
				return Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'full' ) );
				break;
			case self::DATE_LONG :
				return Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'long' ) );
				break;
			case self::DATE_MEDIUM :
				return Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'medium' ) );
				break;
			case self::DATE_SHORT :
				return Zend_Locale_Data::getContent ( $locale, 'date', array ('gregorian', 'short' ) );
				break;
			case self::TIMES :
				return Zend_Locale_Data::getContent ( $locale, 'time' );
				break;
			case self::TIME_FULL :
				return Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'full' ) );
				break;
			case self::TIME_LONG :
				return Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'long' ) );
				break;
			case self::TIME_MEDIUM :
				return Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'medium' ) );
				break;
			case self::TIME_SHORT :
				return Zend_Locale_Data::getContent ( $locale, 'time', array ('gregorian', 'short' ) );
				break;
			case self::DATETIME :
				return Zend_Locale_Data::getContent ( $locale, 'datetime' );
				break;
			case self::DATETIME_FULL :
				return Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'full' ) );
				break;
			case self::DATETIME_LONG :
				return Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'long' ) );
				break;
			case self::DATETIME_MEDIUM :
				return Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'medium' ) );
				break;
			case self::DATETIME_SHORT :
				return Zend_Locale_Data::getContent ( $locale, 'datetime', array ('gregorian', 'short' ) );
				break;
			case self::ATOM :
			case self::RFC_3339 :
			case self::W3C :
				return "yyyy-MM-DD HH:mm:ss";
				break;
			case self::COOKIE :
			case self::RFC_850 :
				return "EEEE, dd-MM-yyyy HH:mm:ss";
				break;
			case self::RFC_822 :
			case self::RFC_1036 :
			case self::RFC_1123 :
			case self::RSS :
				return "EEE, dd MM yyyy HH:mm:ss";
				break;
		}
		
		return $token;
	}
}
